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  • 51.
    Andreason, Ellen
    Dalarna University, School of Technology and Business Studies, Construction.
    Grundvattenhantering i vägskärning: Överväganden, problem och bedömningar kring grundvattnet genom planerandet och byggandet2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Questions and problems related to groundwater management are important in road construction, especially at a cutting slope. The thesis describes the problems encountered during the construction of a road caused by high levels of groundwater. The aim of the thesis was to follow up considerations, problems and assessments considering groundwater connected to the building phase. Four specific aims were formulated; description of erosion control and of the assessments made considering groundwater and its effect on the construction, monitoring groundwater levels during the building phase and to do a simple theoretical calculation of the groundwater levels. 

    To meet the objective several methods were selected, literature review, surveys, interviews with people professionally related to the project and field measurements of groundwater tables.

    Measures to prevent erosion can be divided into vegetative and landscaped, either with soil and rock fills on the slopes or with various ditches. During the project, the design for the road and hillsides changed. Problems with groundwater and erosion have been important for the modified construction. Groundwater levels outside the intersection first increased, probably due to the deforestation and then dropped during the excavation. All but one pipe at the intersection show a lowering of the groundwater during the excavations and a smaller increase during snowmelt than in previous years. The calculated level of groundwater shows in one pipe a level far below the measured, indicating a continuing decrease, in the other pipe a higher level is calculated.

    Advanced vegetative erosion control systems are relative uncommon in Sweden today. Measurements of the groundwater tables should be carried out for a long time to provide a reliable reference level. Knowledge of the soils in the cutting intersection is important in the context of groundwater management together with a sufficient communication between those involved in the construction process. The groundwater levels in the intersection will probably continue its declining trend. Reliable calculations of groundwater tables are complex and their result can still be questioned.  

  • 52.
    Andrée Back, Johan
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Rolin, Tomas
    Dalarna University, School of Technology and Business Studies, Construction.
    Behovsstyrd ventilation: En fallstudie för zonstyrd ventilation i ett flerbostadshus2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction sector accounts for a large part of the primary energy use globally. In order to prevent global warming and to achieve the goals set by Sweden together with the EU, major changes are required in the sector. Energy requirements to heat and cool properties is an important part of this change and for people's well-being. The problem with many of today's system is that they are using more energy than needed and energy efficiency is a must to achieve the goals. Through innovative and smart systems, human needs can be safeguarded while energy requirements is reduced. The purpose was to investigate, through a case study, whether a new ventilation system for apartment buildings could make energy consumption more efficient while at the same time a high indoor comfort could be obtained. Only one apartment is considered which is located in Hedemora, Dalarna. The method was to install a demand-controlled ventilation system in the apartment and measure air quality, air temperature and air flow rate with the help of sensors The new ventilation system is then compared with two common ventilation strategies (extract air and natural ventilation).The energetic evaluation is based on measured air flow rates solely. The result was then compared to government recommendations regarding carbon dioxide levels. The measurement data shows that the demand-controlled ventilation system in most cases reaches the recommendations while the energy demand is lower. An important conclusion from the degree thesis is that ordinary ventilation strategies such as natural draft and exhaust air give a worse indoor climate compared to the demand-controlled system.

  • 53. Andrén, Lars
    et al.
    Persson, Tomas
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Lennermo, Gunnar
    Handbok för kombinerade sol- och biovärmesystem: Teknik - System - Ekonomi2012Report (Other academic)
    Abstract [sv]

    Handboken beskriver olika solfångarkonstruktioner och solvärmekretsens ingående komponenter och ger en grundlig inblick i ackumulatortankens konstruktion och funktion. I boken finns förslag på systemutformning, olika tekniska lösningar och hur systemen bör styras och regleras. Handboken beskriver i första hand utformning-lösning-styrning av kombinationen sol- och pelletsvärme, men tar även upp solvärme i kombination med vedpannor, värmedrivna vitvaror och värmepumpar. Värmesystem med vattenburen värme är utmärkta att kombinera med solvärme, men det är i de flesta fall enklare att få till bra lösningar vid nyinstallation, än vid komplettering av befintlig anläggning. När solvärme och pelletsvärme ska kombineras finns det många alternativ till systemutformning. Det är viktigt att vattenburna pelletssystem utformas korrekt och kombineras på rätt sätt med solvärme för att komforten ska bli hög och elanvändningen låg. Vattenmantlade pelletskaminer med ett vattenburet värmesystem är extra intressant i kombination med solvärme. När eldningen upphör i samband med att värmebehovet avtar kan solvärmen ta över. En generell slutsats är att konventionella svenska pelletspannor med inbyggd varmvattenberedning inte är lämpliga i kombination med solvärmesystem. Den typen av bränslepannor ger komplicerade systemlösningar, höga värmeförluster och det är svårt att åstadkomma en tillräckligt bra temperaturskiktning i ackumulatortanken om varmvattenberedning sker i pannan. Solvärme för varmvattenberedning kan vara ett enkelt och bra komplement till pelletskaminer som genererar varmluft. För solvärmesystem är det viktigt att kraftig temperaturskiktning erhålls när värmelagret laddas ur. Det betyder att ackumulatortankens (eller varmvattenberedarens) nedre vattenvolym ska kylas ner till temperaturer som ligger nära ingående kallvattentemperatur. Ackumulatortankens mellersta del bör kylas till samma temperatur som radiatorreturen. Vid design av solfångarkretsen måste överhettning och stagnation kunna klaras utan risk för glykolnedbrytning eller andra skador på värmebärare eller rörkrets (och andra komponenter i kretsen). Partiell förångning minskar risken för att glykolen skadas då solfångaren når höga stagnationstemperaturer. Solfångarens glykolblandning tillåts koka (förångas) på ett kontrollerat sätt så att endast ånga blir kvar i solfångaren. Vätskevolymen i solfångaren samlas upp i ett större expansionskärl och systemet återfylls när vätskan kondenserar. Dränerande solfångarsystem med enbart vatten är ett möjligt alternativ till konventionella solfångare. De kräver en större noggrannhet vid installationen, så att sönderfrysning undviks. Dränerande systemlösningar är relativt ovanliga i Sverige. Om solfångaren under senhöst-vinter-tidig vår kan arbeta med att förvärma kallvatten från 10 till 20 ºC erhålls en betydligt bättre verkningsgrad på solfångaren (och framför allt ökar värmeutbytet då drifttimmarna ökar väsentligt) än om radiatorreturen (som i bästa fall ligger på temperaturnivån 30 - 40 ºC) ska förvärmas. Därför bör radiatorreturen placeras en bra bit upp från botten i ackumulatortanken och tappvarmvattnet ska förvärmas i en slinga som börjar i tankens botten. Om det finns ett VVC-system måste systemet anslutas på ett speciellt sätt så att ackumulatortankens temperaturskiktning inte störs. En viktig parameter vid ackumulatortankens utformning är att värmeförlusterna hålls låga. Det är viktigt för att klara tappvarmvattenlasten med solvärme under mulna perioder sommartid (men också för att hålla energianvändningen låg). I moderna hus, där ackumulatortanken i regel placeras i bostaden, blir det en komfortfråga att undvika övertemperaturer i det rum där värmelagret placeras. En bra standard på isoleringen (med minimerade värmeförluster) kräver att det finns ett lufttätt skikt över hela isoleringen som dessutom sluter tätt mot röranslutningar. Ofrivillig självcirkulation i anslutande kretsar som kan kyla av och blanda om ackumulatortankens vattenvolym, bör förhindras med backventiler och nedböjning av rören i isolerskiktet eller direkt utanför tanken.

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  • 54.
    Angantyr, Anders
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Lågenergibyggande i Dalarna mars 20122012Report (Other academic)
    Abstract [sv]

    Inom ramen för projektet Energi- och miljökompetenscentrum vid Högskolan Dalarna har en kortare studie av lågenergibyggande i Dalarna gjorts. Syftet med rapporten är att ge en sammanställning av det aktuella läget på området i Dalarna.

    Det finns idag ett flertal bygginitiativ, både privata och allmännyttiga, i Dalarna där man ansträngt sig när det gäller energihushållning. En handfull av dessa kommer nog att uppfylla passivhuskraven enligt FEBY, exakt hur många går dock inte att säga pga infomationsbrist och med tanke på osäkerheten i energiberäkningarna.

    En annan slutsats är att medvetenheten om lågenergibyggande på kommunal och allmännyttig nivå är i allmänhet god och att energihushållning är ett område som ges stort fokus vid den nybyggnation som sker.

    När det gäller det privata byggandet av villor så sker det mesta av byggandet enligt hustillverkarnas typspecifikationer. Då tak, grund och ventilationssystem oftast i princip är samma som för passivhus kan det konstateras att egentligen ganska små förändringar i konstruktion och utförande av detta byggande skulle kunna ge hus enligt FEBYs passivhuskrav eller åtminstone minienergihuskrav.

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  • 55.
    Appelgren, Linnéa
    et al.
    Dalarna University, School of Technology and Business Studies, Graphic Arts Technology.
    Oldhammer, Elina
    Dalarna University, School of Technology and Business Studies, Graphic Arts Technology.
    Barnbok om AST – Autismspektrumtillstånd: Processen bakom skapandet av en informativ barnbok2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today you can read a lot about Autism spectrum disorder, but most of the

    literature is for the people that already have the diagnosis or the people around

    them and some of the books come from people who have the diagnosis

    themselves. What we think is missing on the market today is a book for children

    who meet people with ASD in everyday life. Therefore we created a children’s

    book about ASD. We believe it’s important for children without knowledge to

    understand their classmates with ASD. In an educational way they should be

    able to read and understand what it means to have ASD.

    A background study was made to gain a better understanding of ASD and how

    to write a children’s book. A survey was also made to find out people’s general

    perception and knowledge about ASD. After the background study we designed

    a children’s book for children in the age of 7–9 years.

    To test our bookprototype we met class 3A and 3B of Hälsinggårdsskolan in

    Falun. They got to read the book and afterwards they answered questions about

    what they learned and thought about the book.

    The test of our bookprototype showed that the audience appreciated the book

    and that they learned and had a better understanding of people with ASD.

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  • 56.
    Arguello, Nicolay
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Iñiguez, Enric
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Renewable Energy Emergency Microgrid Optimization in Ludvika2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the community of Ludvika, a Renewable Energy Emergency Microgrid (REEM) has been defined to provide back-up power during crisis situations. An Energy Storage System (ESS) was designed to support the main loads of the Microgrid in the first working hours. Additionally, the ESS will start-up the hydro power station, which will replace the power supply from the battery after the set-up period. However, the necessity of understanding the operation of the major components, such as the photovoltaic (PV) system and the ESS, of the REEM in normal conditions is imperative.

    This study analyses a variety of scenarios to evaluate how the renewable energy of an isolated system can be managed. Alternatives for increasing self-consumption of PV power and reduce feed-in power in the REEM are investigated. All the solutions consider the complete system design and an additional economic analysis for supporting the decision-making. The results show that selling the energy to the grid is the best economic solution, followed by the distribution of energy. However, the difference of 0.5 % in the total net present cost (TNPC) makes the distribution system, including the ESS, an option to be considered. In the upcoming years, changes on the amount of energy produced by the PV system or increasing the battery capacity usage in normal operation can become more feasible.

  • 57.
    Argårds, Andreas
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Kartläggning av ytjämnheten efter kallvalsning för olika kallvalsade kvalitéer samt trimvalsningens påverkan på ytjämnheten2010Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Syftet med detta arbete är att kartlägga ytjämnheten på stålbanden efter kallvalsning samt hur den erhålla ytjämnheten påverkas av trimvalsningen. Detta för att undersöka om det är möjligt att minska ner användandet av någon valsyta i Tandemverket vid SSAB Borlänge. Genom att mäta ytjämnheten på stålband av olika kallvalsade kvalitéer efter kallvalsning och trimvalsning, mäta ytråheten på texturerade valsar före och efter användning samt genomföra test med nya ytkombinationer har ett antal resultat genererats. Två test där Docol 200 band som skulle levereras med bandyta 23 valsades med en grövre yta i Tandem (valsyta 48 istället för 34) än vad som är brukligt och sedan trimvalsades med ordinarie valsyta visade att det är möjligt att klara kraven på Ra-värde för bandyta 23 även på band som kallvalsats med en grövre valsyta än i vanliga fall. Dock är det inte säkerställt att kraven för yta 23 alltid kan uppnås på band kallvalsade med grövre valsyta. Trimvalsning med valsyta 57 i den kontinuerliga glödgningslinjen har ingen betydande påverkan på ytjämnheten för Docol 600 & 800 DP, dock påverkar den ytan för Docol 200 eftersom att dessa band har mindre spridning i Ra-värde efter trimvalsning jämfört med innan. Trimvalsning med valsyta 57 höjer toppantalet på bandens yta. Band av en högre hållfasthetsklass får lägre Ra-värde jämfört mot mjukare stålsorter. Band med stor tjockleksreduktion i Tandem får lägre Ra-värde, detta gäller speciellt Docol 200 där trenden är tydligast. Ra-värdet på de texturerade valsarna i Tandem sjunker mycket i början när de används, test har visat att redan under kalibreringen kan Ra-värdet minska med 0,8 µm – 1,3 µm.

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  • 58.
    Argårds, Mattias
    Dalarna University, School of Technology and Business Studies, Construction.
    Analys av lägenhetsskiljande bjälklag: Fallstudie av produktion av flerbostadshus i Sälenfjällen2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In construction of apartments several parameters determines the choice of production method. Costs and production time for the various operations are two important parts , As early as the planning stage it is important to have a clear picture of the different solutions' and its prerequisites to simplify the choice of production method.

    For new construction projects in Sälenfjällen the tight production times makes it important to know whether any solution could involve considerable delays in production time. On the other hand faster construction methods may also lead to higher costs.

    The thesis has been limited to four different floor constructions which are Finjas “Combi bjälklag”, “plattbärlag”, cross laminated timber and Dala cements “Daladekk”. The calculation has been linked to a reference building in Sälenfjällen and a supposed new production of four similar buildings.

    With the help of the structural design calculations were carried out to estimate the costs each approach brings, it also performed one simple analysis of the time spent.

    The result shows that it is best economical to build with "plattbärlag", followed by cross laminated timber. At the same time plattbärlaget and its construction has a risk for delayed production times, which mean it may be advantageous to chose the solution with cross laminated timber.

  • 59.
    Arnberg, Jerker
    Dalarna University, School of Technology and Business Studies, Electrical Engineering.
    Zigbee för längre avstånd2006Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    I dag går utvecklingen av trådlösa nätverk snabbt framåt. Zigbee är en helt ny teknik som bygger på IEEE 802-15-4 standarden. Zigbee utvecklades av the Zigbee Alliance som består av en rad stora elektronikföretag. Zigbee är en teknik som inriktar sig på låg energiförbrukning och låg kostnad. Tekniken är tänkt att användas för att ställa in och läsa av sensorer av olika slag. Denna rapport är ett resultat av ett examensarbete som går ut på att utreda om Zigbee tekniken kan användas för lite längre avstånd. Arbetet resulterade i två demoapplikationer för ett enkel zigbee system, och färdigskriven kod för en möjlighet att använda Zigbee för länge avstånd.

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  • 60.
    Ashraf, Ali Junaid
    Dalarna University, School of Technology and Business Studies, Electrical Engineering.
    DC Motor Speed Control via Fuzzy / Pole Placement / PI Controller2010Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report presents a new way of control engineering. Dc motor speed controlled by three controllers PID, pole placement and Fuzzy controller and discusses the advantages and disadvantages of each controller for different conditions under loaded and unloaded scenarios using software Matlab. The brushless series wound Dc motor is very popular in industrial application and control systems because of the high torque density, high efficiency and small size. First suitable equations are developed for DC motor. PID controller is developed and tuned in order to get faster step response. The simulation results of PID controller provide very good results and the controller is further tuned in order to decrease its overshoot error which is common in PID controllers. Further it is purposed that in industrial environment these controllers are better than others controllers as PID controllers are easy to tuned and cheap. Pole placement controller is the best example of control engineering. An addition of integrator reduced the noise disturbances in pole placement controller and this makes it a good choice for industrial applications. The fuzzy controller is introduce with a DC chopper to make the DC motor speed control smooth and almost no steady state error is observed. Another advantage is achieved in fuzzy controller that the simulations of three different controllers are compared and concluded from the results that Fuzzy controller outperforms to PID controller in terms of steady state error and smooth step response. While Pole placement controller have no comparison in terms of controls because designer can change the step response according to nature of control systems, so this controller provide wide range of control over a system. Poles location change the step response in a sense that if poles are near to origin then step response of motor is fast. Finally a GUI of these three controllers are developed which allow the user to select any controller and change its parameters according to the situation.

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  • 61.
    Awda, Fadi
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Omkonstruktion av luftkylning för enfasreaktor2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The task of this thesis was to review the failure of three reactor units that were caused by

    moisture and dirt that entered the reactor through the cooling system. The purpose was to find

    a solution that would allow the reactor to stay on site without being affected by moisture or

    dirt.

    The company did not have resources to provide a quick solution for the project and therefore

    time and money is a big factor. The specifications from the customer strictly forbid any

    assemblies outside of the site and that nothing in their surroundings are affected by the work.

    To come to a conclusion the reactor had to be broken down to pieces and after that concepts

    were made to affect the environment around the reactor or the design.

    The safety that the customer requires is that the cooling equipment should be at least as

    efficient as the current one and that we make sure that this type of failure will not be repeated.

    The problem was solved by adding a temperature device that measures the heat in the reactor

    that controls the fan and redirects the airflow inside the reactor through redesign to make sure

    that moisture and dirt won't occur inside the reactor – to avoid internal flash over.

  • 62.
    Aylott, Benjamin
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Techno-Economic Evaluation of Distributed Generation within a Community Smart Grid with Demand Side Response Using HOMER2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this study the distributed generation of renewable energy, primarily photovoltaic power, and consumption of energy within a geographically dispersed smart grid or ‘virtual micro grid’ is simulated using a model based around the HOMER Pro software with the aim of gaining insight into the economic and environmental performance of the system under different assumptions about the configurations of the generators and the presence of low carbon technologies such as heat pumps and electric vehicles. Demand side response for the purpose of reducing carbon emissions was also investigated as part of this.

    As well as simulating the system within HOMER, the study involved constructing a representative load profile for 200 domestic consumers and other loads using existing data, implementing a model for demand side response, using a range of detailed technical and environmental data to configure the HOMER model, and creating custom plotting tools. These features were connected in a data analysis pipeline written in Python included as part of the submission.

    The study found that to improve the environmental and economic performance of the system increasing the amount of renewable generation should be prioritized over other measures, such as demand side response. PV was the easiest to add due to lower upfront costs (compared to battery storage systems and mid-scale wind turbines) and lower financial and regulatory overheads. Carbon emissions were found to be minimized for around 3.5kW of PV per household in this scenario. Including a single mid-scale wind turbine was found to have the potential to greatly increase renewable penetration, and reduce carbon emissions and the cost of energy due to the complementary nature of PV and Wind power production. Battery storage at low penetrations was found to have little impact, but can make a large impact at high penetration but at significant financial expense.

    A range of battery products was also investigated for their suitability for use within the project and future schemes and were evaluated by locating them in the Renewable Fraction/LCOE plane.

    The inclusion of low carbon technologies such as heat pumps and electric vehicles was found to have some negative impact on the performance where only PV is present in the smart grid with little evidence that it can make better use of the renewable power due to poor matching with the available PV generation.

  • 63.
    Azad, Mohammad
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Evaluation of an Energy System for multi-family houses with Combination of Exhaust Air Heat Pump and PV: Case Study: Demonstration Building of The EU Energy Matching Project, Sweden-Ludvika2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis investigated application of the heat recovery ventilation using an exhaust air heat pump and a roof top photovoltaic (PV) system for a group of three multi-family houses located in Ludvika, Sunnansjö. The buildings in the existing condition have mechanical ventilation and a centralized heating system consists of a pellet boiler as the main source and an oil boiler as back up.

    Exhaust air heat pump (EAHP) has been known by the previous relevant researches as an effective solution to promote the energy efficiency in the buildings. Furthermore, reduction in PV cost has made the PV as a financially viable option to be contributed in supplying electricity demand.

    In this respect, this thesis aimed to calculate the potential of energy saving in the case study using the combination of EAHP and PV. For this purpose, the buildings and the proposed energy system were simulated to enable the comparison of energy demand before and after the renovation. The simulation was gradually progressed through several phases and each stage created the prerequisites of the next.

    Since the buildings were relatively similar in terms of boundary conditions, one of the buildings were initially modeled and the concluded space heating (SH) demand was extrapolated to the three buildings scope. The simulation of the building was done using 3dimensional thermal model offered by Trnsys3d. The primary results were also calibrated against the available annual fuel consumption data. In the second phase, a pre-developed TRNSYS model of the energy system was completed using the result of previous step as the total SH demand as well as the estimated domestic hot water (DHW) consumption from a stochastic model. This simulation produced the electricity demand profile of the heat pump when the heat pump provided the total heat demand. Subsequently, the electricity consumption of the flats and operational equipment were estimated using stochastic model and available monthly measurement, respectively.

    Since the feasibility and optimal placement of 74 𝑘𝑊 PV modules offered for these buildings had been already examined by the author in another study, the final simulation were performed in an hourly basis considering PV production and total electricity demand; i.e. EAHP, flats consumption and operational equipment.

    The results of the simulation showed that 21 % of total electricity demand during a year could be supplied by the proposed PV system even without any electrical storage, whereas 74 % of total yearly PV production is consumed by the local loads. The results also proved that removing old inefficient oil boiler and supplementing the pellet boiler with the combination of EAHP and PV could mitigate the annual purchased energy (including electricity and pellet) by approximately 40 % compared to the current condition.

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  • 64.
    Azizoğlu, Yağız
    Dalarna University, School of Technology and Business Studies, Materials Technology. Luleå University of Technology.
    Modeling of Cold Pilgering of Tubes2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Cold pilgering is a challenging tube forming process in terms of modeling due to the complexity in kinematic of tools, friction condition and material behavior. The process development has mostly been based on simple formulas and costly full-scale tryouts. The aim in this study is to develop validated Finite element models of cold pilgering to increase the understanding of influence of the process parameters on the produced tubes.

    In the course of this thesis, three-dimensional mechanical and thermo-mechanical Finite element models of cold pilgering were developed. The commercial code MSC.Marc was used in the simulations. General 3D models are needed to be able to capture asymmetric deformation in cold pilgering. It was found that tool deflections together with elastic deformation of roll dies have considerable influence on the rolling force. Furthermore, the strain rate and temperature effects on the response of the material and thereby on the rolling force were evaluated.

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  • 65.
    Azizoğlu, Yağız
    et al.
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    Gardsback, M.
    Sjoberg, B.
    Lindgren, L. -E
    Finite element modelling of cold pilgering of tubes2015In: Proceedings of the 8th International Conference on Computational Plasticity - Fundamentals and Applications, COMPLAS 2015, 2015, p. 716-726Conference paper (Refereed)
    Abstract [en]

    Cold pilgering is a cold forming process used during manufacturing of seamless tubes. The tube with a mandrel inside is fed forward and rotated in stepwise increments, while the roll stand moves back and forth. The total plastic deformation of the tube is such that the cross-sectional area of the tube decreases and the length of the tube increases during the process. However, this is performed in many small incremental steps, where the direction of deformation in a material point changes at each stroke. Most published models of cold pilgering use simplified material models. In reality, the flow stress is dependent on temperature, strain rate, strain history and microstructure. In this work, temperature and strain rate distributions are computed, using a 3D thermo-mechanical FE model, and the influence of temperature and strain rate on the rolling force is investigated. The Johnson-Cook model is employed to describe the flow stress using isotropic hardening. The results show that strain rate and temperature have a significant influence on the roll separation force.

  • 66.
    Azizoğlu, Yağız
    et al.
    Dalarna University, School of Technology and Business Studies, Materials Technology. Luleå University of Technology.
    Gärdsback, M.
    Yamanaka, A.
    Kuwabara, T.
    Lindgren, L. -E
    Work hardening during alternating load directions of 316L SS2018In: Procedia Manufacturing, E-ISSN 2351-9789, Vol. 15, p. 1777-1784Article in journal (Refereed)
    Abstract [en]

    Understanding and modelling the plastic behavior of a material are essential for simulation and design of metal forming processes. Cold pilgering of tubes is a process with very complex strain history with alternating loading direction. This makes evaluation of the work hardening challenging. Cold deformation applied in a single direction predominantly exhibit work hardening, while changes of the loading direction may even cause softening in other directions. The influence of alternating loading directions on work hardening has been experimentally investigated for 316L stainless steel (SS). Cubic specimens were cut out from the preform of the tube. The specimens are subjected to uniaxial compressions in alternating directions along two perpendicular axes. From the results, a cyclic elastic-plastic constitutive model based on a Chaboche-type approach is calibrated and implemented in the commercial finite element code MSC.Marc.

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  • 67.
    Azizoğlu, Yağız
    et al.
    Dalarna University, School of Technology and Business Studies, Materials Technology. Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Gärdsback, Mattias
    Sandvik Materials Technology, R&D, Sandviken..
    Sjöberg, Bengt
    Sandvik Materials Technology, R&D, Sandviken..
    Lindgren, Lars-Erik
    Luleå University of Technology.
    Finite element analysis of cold pilgering using elastic roll dies2017Conference paper (Refereed)
    Abstract [en]

    A finite element model of cold pilgering with elastic roll dies have been developed and used to investigate the influence of roll die deformation on the material flow, contact region, roll separating force and tube dimensions. Full scale experiments were performed to validate the contact surface and tube dimensions. The results show that the influence of roll die flattening is not significant on the contact length. However, elastic deformation of roll die has strong influence on both the wall thickness reduction and roll separating force. Thus it is recommended to consider elasticity of roll dies when forces and tube dimensions are estimated.

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  • 68.
    Azizoğlu, Yağız
    et al.
    Dalarna University, School of Technology and Business Studies, Materials Technology. Luleå University of Technology.
    Gärdsback, Mattias
    Sjöberg, Bengt
    Lindgren, Lars-Erik
    Finite element modeling of tube deformation during cold pilgering2016In: MATEC Web of Conferences, 2016, Vol. 80, article id 15004Conference paper (Refereed)
    Abstract [en]

    A three-dimensional finite element model of cold pilgering of stainless steel tubes is developed in this paper. The objective is to use the model to increase the understanding of forces and deformations in the process. The focus is on the influence of vertical displacements of the roll stand and axial displacements of the mandrel and tube. Therefore, the rigid tools and the tube are supported with elastic springs. Additionally, the influences of friction coefficients in the tube/mandrel and tube/roll interfaces are examined. A sensitivity study is performed to investigate the influences of these parameters on the strain path and the roll separation force. The results show the importance of accounting for the displacements of the tube and rigid tools on the roll separation force and the accumulative plastic strain.

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  • 69.
    Badri, Seyed Ali Mohammad
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Simulation of Photovoltaic Panel Production as Complement to Ground Source Heat Pump System2013Independent thesis Advanced level (degree of Master (Two Years)), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    This master thesis presents a new technological combination of two environmentally friendly sources of energy in order to provide DHW, and space heating. Solar energy is used for space heating, and DHW production using PV modules which supply direct current directly to electrical heating elements inside a water storage tank. On the other hand a GSHP system as another source of renewable energy provides heat in the water storage tank of the system in order to provide DHW and space heating. These two sources of renewable energy have been combined in this case-study in order to obtain a more efficient system, which will reduce the amount of electricity consumed by the GSHP system.The key aim of this study is to make simulations, and calculations of the amount ofelectrical energy that can be expected to be produced by a certain amount of PV modules that are already assembled on a house in Vantaa, southern Finland. This energy is then intended to be used as a complement to produce hot water in the heating system of the house beside the original GSHP system. Thus the amount of electrical energy purchased from the grid should be reduced and the compressor in the GSHP would need fewer starts which would reduce the heating cost of the GSHP system for space heating and providing hot water.The produced energy by the PV arrays in three different circuits will be charged directly to three electrical heating elements in the water storage tank of the existing system to satisfy the demand of the heating elements. The excess energy can be used to heat the water in the water storage tank to some extent which leads to a reduction of electricity consumption by the different components of the GSHP system.To increase the efficiency of the existing hybrid system, optimization of different PV configurations have been accomplished, and the results are compared. Optimization of the arrays in southern and western walls shows a DC power increase of 298 kWh/year compared with the existing PV configurations. Comparing the results from the optimization of the arrays on the western roof if the intention is to feed AC power to the components of the GSHP system shows a yearly AC power production of 1,646 kWh.This is with the consideration of no overproduction by the PV modules during the summer months. This means the optimized PV systems will be able to cover a larger part of summer demand compared with the existing system.

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  • 70.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    ClimateWell TDC with District Heat2010Report (Other academic)
    Abstract [en]

    The PolySMART demonstration system SP1b has been modeled in TRNSYS and calibrated against monitored data. The system is an example of distributed cooling with centralized CHP, where the driving heat is delivered via the district heating network. The system pre-cools the cooling water for the head office of Borlänge municipality, for which the main cooling is supplied by a 200 kW compression chiller. The SP1b system thus provides pre-cooling. It consists of ClimateWell TDC with nominal capacity of 10 kW together with a dry cooler for recooling and heat exchangers in the cooling and driving circuits. The cooling system is only operated from 06:00 to 17:00 during working days, and the cooling season is generally from mid May to mid September. The nominal operating conditions of the main chiller are 12/15°C.

    The main aims of this simulation study were to: reduce the electricity consumption, and if possible to improve the thermal COP and capacity at the same time; and to study how the system would perform with different boundary conditions such as climate and load.

    The calibration of the system model was made in three stages: estimation of parameters based on manufacturer data and dimensions of the system; calibration of each circuit (pipes and heat exchangers) separately using steady state point; and finally calibration of the complete model in terms of thermal and electrical energy as well as running times, for a five day time series of data with one minute average data values. All the performance figures were with 3% of the measured values apart from the running time for the driving circuit that was 4% different. However, the performance figures for this base case system for the complete cooling season of mid-May to midSeptember were significantly better than those for the monitoring data. This was attributed to long periods when the monitored system was not in operation and due to a control parameter that hindered cold delivery at certain times. 

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  • 71.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    European resarch school on large scale solar thermal - SHINE2014In: Solar District Heating 2014, Hamburg, Germany, 2014Conference paper (Other academic)
    Abstract [en]

    The Solar HeatIntegration NEtwork (SHINE) is a European research school in which 13 PhDstudents in solar thermal technologies are funded by the EU Marie-Curie program.It has five PhD course modules as well as workshops and seminars dedicated to PhDstudents both within the project as well as outside of it. The SHINE researchactivities focus on large solar heating systems and new applications: ondistrict heating, industrial processes and new storage systems. The scope ofthis paper is on systems for district heating for which there are five PhDstudents, three at universities and two at companies. The PhD students allstarted during the early part of 2014 and their initial work has concentratedon literature studies and on setting up models and data collection to be usedfor validation purposes. The PhD students will complete their studies in2017-18.

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  • 72.
    Bales, Chris
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Andersen, M.
    Bava, F.
    Louvet, Y.
    Peréz de la Mora, N.
    Sotnikov, A.
    Shantia, A.
    SHINE Doctoral School: Results from six PhD studies on large scale solar thermal2016In: 4th International Solar District Heating Conference, 2016Conference paper (Other academic)
    Abstract [en]

    The Solar Heat Integration NEtwork (SHINE) is a European research school in which 13 PhD students in solar thermal technologies are funded by the EU Marie-Curie program. It has five PhD course modules as well as workshops and seminars dedicated to PhD students both within the project as well as outside of it. The SHINE research activities focus on large solar heating systems and new applications: on district heating, industrial processes and new storage systems. The scope of this paper is on systems for district heating for which there are six PhD students, five at universities and one at a company. The initial work concentrated on literature studies and on setting up initial models and measurement setups to be used for validation purposes. The measurements have been used for validating simulation models, including those used for extending the capabilities of the planning tool Polysun to simulate smaller district heating systems. Some results of these studies are presented in the paper. The PhD students will complete their studies in 2017-18.

  • 73.
    Bales, Chris
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Betak, Jan
    Broum, Michal
    Chèze, David
    Cuvillier, Guillaume
    Haberl, Robert
    Hafner, Bernd
    Haller, Michel
    Poppi, Stefano
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Weidinger, Alexander
    Optimized solar and heat pump systems, components and dimensioning: Deliverable 7.3 - MacSheep - New Materials and Control for a next generation of compact combined Solar and heat pump systems with boosted energetic and exergetic performance2015Report (Other (popular science, discussion, etc.))
    Abstract [en]

    This report describes the optimised solar and heat pump systems developed in the MacSheepproject as well as the simulation results for these systems. Four systems have been developed by four different development groups, each with one private company participating. The development groups have chosen different types of systems as well as different target loads for their systems, which give a wide coverage of the potential markets. The aim of the project was to achieve a 25% performance increase compared to state of the art systems, while being cost-competitive compared to the state of the art.Two reference state of the art solar and heat pump systems have been defined, modelled,and simulated to derive benchmark electricity demands and SPF values for the boundary conditions that were defined for the MacSheep project. The reference systems usedtheground (boreholes) orair as a heat source for the heat pump. The chosen boundary conditions were the climates of Zurich and Carcassone, arealistic DHW load,and two buildings, one representing a modern low energy building (SFH45) and one representing an existing building (SFH100). These reference systems and boundary conditions were defined within the first year of the project, and are used throughout the project.New components were developed for the MacSheepsolar and heat pump systems and these developments are reported in the reportsof work packages 3 –6. Component models have been programmed and validated with laboratory measurements.In this report, simulation results for the four MacSheep systems arecompared to the relevant reference system in order to quantify the expected performance increase. These simulations include the component models with their validated parameters and performance obtained from phase 3 of the project.In addition, the costs of the systemswere estimated. The key performance indicator for the final system developments was defined as a figure for electric savings (25%) compared to the state of the art at competitive (i.e. comparable) cost. Therefore, cost-savings that were achieved for some of the components that were developed were allowed to be compensated by increased cost for other components or increased collector areasin order to show the project's achievements in the light of the defined key performance indicator.At present, the updated simulations show electric savings of 17%, 24%, 26%, and 30%, respectively, for the different developments and the different target heat loads.Threeof these systems will be built and tested during 2015,using the whole system test method that was further developed within the MacSheep project (see report D2.3 for more details). The results from these tests will give benchmark energy used of these systems both for the test sequence itself but also on an annual base. In addition, the simulation models described in this report will be verified against the measurements and then used for annual simulations for otherboundary conditionsthan the once that are represented in the test sequence.

  • 74.
    Bales, Chris
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Betak, Jan
    Broum, Michal
    Chèze, David
    CEA INES.
    Cuvillier, Guillaume
    Haberl, Robert
    Institut für Solartechnik SPF Hochschule für Technik HSR.
    Haller, Michel Y.
    Institut für Solartechnik SPF Hochschule für Technik HSR.
    Hamp, Quirin
    Poppi, Stefano
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Weidinger, Alexander
    Final report on storage developments in WP - Deliverable 5.4: MacSheep - New Materials and Control for a next generation of compact combined Solar and heat pump systems with boosted energetic and exergetic performance2015Report (Other (popular science, discussion, etc.))
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  • 75.
    Bales, Chris
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Gustafsson, Marcus
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Chiara, Dipasquale
    Roberto, Fedrizzi
    Alessandro, Bellini
    Matteo, D’Antoni
    Fabian, Ochs
    Georgios, Dermentzis
    Sarah, Birchall
    D2.1c Simulation Results of Reference Buildings2014Report (Other academic)
    Abstract [en]

    This report is the third part of the deliverable D2.1, where the other two parts report on the energy consumption in the building stock in Europe based on the available energy statistics (D2.1a) and the energy policies related to buildings (D2.1b).The aim of this report is to give complementary information about the heating and cooling demands of residential and office buildings based on simulations, so that the many gaps in the energy statistics can be filled and the statistics can be critically evaluated. The methodology results in a complete and consistent overview of the heating and cooling demands in residential and office buildings for seven different climate regions covering the whole of the EU and six different periods of construction, covering pre-1945 to post 2000. In addition, the data for the residential building stock is split into single family houses, small and large multifamily houses, while for offices the results are given for low and high rise offices with 6 or 12 office units per floor.The simulation models have been benchmarked (calibrated) against the energy statistics for each of the seven climate regions based on the aggregated data for the whole residential building stock and then for the office building stock in that climate region (in D2.1a). The methodology derives the aggregated average using weighted averages of data split into periods of construction and typology for both energy statistics and simulation results. The weighting is done based on heated and cooled floor area. As nearly all of the energy statistics are given in terms of consumption, while simulation results were calculated as demand, the demand data were converted to consumption data. One fixed conversion factor was used for heating (average efficiency 0.8) and one for cooling (average EER 2.5). Since the calculated demands strongly depend on the imposed heating or cooling set temperatures, this simulation parameter was varied so that the aggregated simulation result was the same as that for the consumption derived from the energy statistics. The calibrated models were then used to derive the average heating and cooling consumptions of the building stock in the seven climate regions.The methodology has a number of uncertainties, both in terms of the energy statistics as well as in terms of the simplifications and assumptions in the simulation models. During the calibration process a number of inconsistencies have been detected for individual countries and climate regions between simulation results and energy use from statistic data. The mismatches are analytically assessed, showing improvements necessary both in terms of statistic data necessary for reliable energy estimations and data to be gathered in order to guarantee consistent simulations outcomes.Beside the building stock survey completion and statistic data quality assessment, the work is also the basis for the definition of suitable Energy Renovation Packages and Products within the iNSPiRe project. The simulation results will be used to identify which building typologies, periods of construction and climate region have the largest potential for impact on the European scenario. Such information will be used within the iNSPiRe project to define reference Target buildings, as virtual demonstration cases to prove the potential improvements and impacts following the renovation process of a given share of the European building stock.

  • 76.
    Bales, Chris
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Lorenz, Klaus
    Application of Polysun in Teaching Courses in Sweden and in the PhD Program SHINE2016In: SIGES Internationale Konferenz zur Simulation gebäudetechnischer Energiesysteme, 2016, p. 90-95Conference paper (Other academic)
  • 77.
    Bales, Chris
    et al.
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Nielsen, Christian
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Peréz de la Mora, Nicolás
    Sotnikov, Artem
    Louvet, Yoann
    Bava, Federico
    Shantia, Alireza
    Lennermo, Gunnar
    Seven Phd Studies on Solar District Heat2014In: EuroSun 2014 / ISES Conference Proceedings (2014), ISES , 2014Conference paper (Other academic)
    Abstract [en]

    The Solar Heat Integration NEtwork (SHINE) is a European research school in which 13 PhD students in solar thermal technologies are funded by the EU Marie-Curie program. It has five PhD course modules as well as workshops and seminars dedicated to PhD students both within the project as well as outside of it. The SHINE research activities focus on large solar heating systems and new applications: on district heating, industrial processes and new storage systems. The scope of this paper is on systems for district heating for which there are six PhD students, three at universities and two at companies. In addition there is a seventh PhD in a Swedish national research school focused on energy efficiency within district heating networks (Reesbe). The initial work has concentrated on literature studies and on setting up initial models and measurement setups to be used for validation purposes. Some results of these studies are presented in the paper. The PhD students will complete their studies in 2017-18.

  • 78.
    Baranger, Renaud
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Performance Analysis of a Grid-Connected PV System in Borlänge, Sweden2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis aimed to evaluate the performance of the new configuration of the array one of Högskolan Dalarna grid-connected PV system. This PV grid-connected system has been in operation since 1994. The system is composed of two arrays with a rated power of 1.62kW and two inverters of 1.2 kWp. In 2014 the new configuration of array one was composed of 4 strings of 9 modules each. This configuration had twice as much current than array two, and its voltage was halved (180V). The objective was to improve the global performance of the system, mostly under low irradiance conditions. The performance evaluation of the system was conducted according to IEC 61724 standard, and was performed in March and April 2014.

    It appeared that the higher current in array one improved the turn-on power of its inverter. While the inverter of array two started operating at 126W/m² the inverter of array one started at 37W/m². It was also shown that the array yield of array one increased by 1% at low irradiance (0-200W/m²) during the two months of this thesis work. Moreover, the input voltage dependency of the inverter was clearly shown. Halved the voltage in array one increased the inverter efficiency between 1% and 2%. It was shown that the higher current of the array one did not impact the losses of the system. The system losses also decreased between 9.4% and 10.5%. Besides, this work highlighted that arrays’ DC power was probably different. It led to a better performance of array two at high irradiance compare to array one. Eventually the performance ratio of array one was greater than array two during these two months. It reached 63.2% in March and 69.4% in April.

  • 79.
    Barwén Trollvik, Denise
    Dalarna University, School of Humanities and Media Studies, Moving Image Production.
    Shall we dance?: Passion, intimitet och maskulinitet i Masayuki Suos Får jag lov? och Peter Chelsoms Shall We Dance? 2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med det här kandidatexamensarbetet är att undersöka hur den japanska filmen Får jag lov? från 1996, och den amerikanska remaken Shall We Dance? från 2004, skiljer sig från varandra utifrån hur karaktärerna uttrycker maskulinitet, intimitet och passion genom karaktärisering. Karaktärerna som undersöks är den manliga och kvinnliga huvudrollen samt en viktig biroll från varje film. Vidare undersöks även varför skillnaderna uppstår mellan Får jag lov? och Shall We Dance?. Analysen tyder på att skillnaderna i hur maskulinitet, intimitet och passion visas genom karaktärisering i de båda filmerna inte är så stora. Tvärtom så liknar filmerna varandra till stor del i dessa avseenden. Skillnaderna mellan de två filmerna visar sig däremot handla om kulturella skillnader, då filmerna är från två olika länder.

  • 80.
    Bastholm, Caroline
    Dalarna University, School of Technology and Business Studies, Energy Technology. IEA Photovoltaic Power Systems Programme.
    A user guide to simple monitoring and sustainable operation of PV-diesel hybrid systems: Handbook for system users and operators2015Report (Other (popular science, discussion, etc.))
    Abstract [en]

    This report contains a suggestion for a simple monitoring and evaluation guideline for PV-diesel hybrid systems. It offers system users a way to better understand if their system is operated in a way that will make it last for a long time. It also gives suggestions on how to act if there are signs of unfavourable use or failure. The application of the guide requires little technical equipment, but daily manual measurements. For the most part, it can be managed by pen and paper, by people with no earlier experience of power systems.The guide is structured and expressed in a way that targets PV-diesel hybrid system users with no, or limited, earlier experience of power engineering. It is less detailed in terms of motivations for certain choices and limitations, but rich in details concerning calculations, evaluation procedures and maintenance routines. A more scientific description of the guide can be found in a related journal article.

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  • 81.
    Bastholm, Caroline
    Dalarna University, School of Technology and Business Studies, Energy Technology. Uppsala universitet, Fasta tillståndets fysik.
    Micro-grids supplied by renewable energy: Improving technical and social feasibility2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Universal access to electricity stands high on the global agenda and is regarded as essential for positive development in sectors such as health care, education, poverty reduction, food production and climate change. Decentralized, off-grid electrification is deemed an important complement to centralized grid extension. By utilizing a renewable energy source, solar technology for the generation of electricity, photovoltaics (PV) is being considered as a way forward to minimize the environmental problems related to energy use.

    This thesis aims to contribute to improving the technical and social feasibility of PV and PV-diesel hybrid micro-grids for the purpose of providing access to electricity to people in rural areas of countries with low level access to electricity. In line with these general aims, the focus has been to address three questions related to challenges in three phases of rural electrification. The work has a multi-disciplinary approach, addressing mainly technical and social aspects of long-term sustainability of micro-grids, in a local context, and the changes these are intended to generate. One specific micro-grid in Tanzania has been used as a major case study.

    The thesis is developed through three papers, all presenting methodologies or aspects for investigation in rural electrification projects and studies in general, and for PV-diesel hybrid micro-grids in particular. Paper I puts forward a methodology to facilitate non-social scientific researchers to take social aspects increasingly into consideration. Paper II is a guideline to support system users to increasingly apply an evaluation based system operation. Paper III specifically highlights the importance to consider blackouts when investigating how an existing off-grid PV-diesel hybrid system shall be utilized when a national grid becomes available.

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  • 82.
    Bastholm, Caroline
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Using locally available components and local knowledge to build sustainable stand-alone power systems2013In: Symposium Small PV-Applications : rural electrification and commercial use ; Ulm, Germany, June 17th/18th, 2013, Regensburg: Ostbayerisches Technologie-Transfer-Institut eV (OTTI) , 2013Conference paper (Other academic)
    Abstract [en]

    The aim of this paper is to point out benefits as well as disadvantages associated with the use of locally available, not necessarily standardized, components in stand-alone electrical power systems at rural locations. Advantages and challenges arising when the direct involvement in design, construction and maintenance of the power system is reserved to people based in the area of implementation are discussed. The presented research is centered around one particular PV-diesel hybrid system in Tanzania; a case study in which technical and social aspects related to the particular power system are studied.

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  • 83.
    Bastholm, Caroline
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Fiedler, Frank
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Techno-economic study of the impact of blackouts on the viability of connecting an off-grid PV-diesel hybrid system in Tanzania to the national power grid2018In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 171, no 1, p. 647-658Article in journal (Refereed)
    Abstract [en]

    National electrification plans for many countries with a low level of electrification promote the implementation of centralized and decentralized electrification in parallel. This paper explores different ways of utilizing an established off-grid PV-diesel hybrid system when the national grid becomes available. This is a rather unique starting point within the otherwise well-explored area of rural electrification. With particular focus on the impact of blackouts in the national grid, we evaluate the economic viability of some alternatives: to continue to use the off-grid micro-grid, to connect the existing micro-grid with or without battery backup to the national grid, or to use the national grid only. Our simulation results in HOMER demonstrate that with a grid without blackouts, there are few benefits to maintain the existing system. Low grid-connection fees, low tariffs and low revenues from selling excess electricity to the grid contribute to this result despite the fact that the system does not carry any investment costs. With a grid with blackouts, it is beneficial to maintain the system. The extent of blackouts and the load on the system determine which system configuration is most feasible. The results make clear the importance of taking blackouts in the national grid into consideration when possible system configurations are being evaluated. This is rarely quantified in studies comparing different electrification alternatives, but deserves more attention.

  • 84. Bee, Elena
    et al.
    Prada, Alessandro
    Baggio, Paolo
    Psimopoulos, Emmanouil
    Dalarna University, School of Technology and Business Studies, Energy Technology. Uppsala University.
    Air-source heat pump and photovoltaic systems for residential heating and cooling: Potential of self-consumption in different European climates2019In: Building Simulation, ISSN 1996-3599, E-ISSN 1996-8744, Vol. 12, no 3, p. 453-463Article in journal (Refereed)
    Abstract [en]

    Renewable sources will play a key role in meeting the EU targets for 2030. The combined use of an aerothermal source through a heat pump and a solar source with a photovoltaic (PV) system is one feasible and promising technology for the heating and cooling of residential spaces. In this study, a detailed model of a single-family house with an air-source heat pump and a PV system is developed with the TRNSYS simulation software. Yearly simulations are run for two types of buildings and nine European climates, for both heating and cooling (where needed), in order to have an overview of the system behaviour, which is deeply influenced by the climate. The storage system (electrical and thermal) is also investigated, by means of multiple simulation scenarios, with and without the battery and with different water storage sizes. The numerical results provide an overview of the performance of the considered heating and cooling system, as well as the balance of the electrical energy exchange between the grid, the building, and the PV array.

  • 85.
    Bengtsson, Sebastian
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    Påverkan på mätresultatet av slagprovets läge i slagprovmaskinen2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The project assumes that test whether the height of the smaller pendulum test dimensions (10 mm x 7.5 mm, 10 mm x 5 mm and 10 mm x 2.5 mm) is irrelevant to the outcome and to correct for the internal friction in the pendulum test machine. This is because the firm recently received accreditation for the new testing standard. The different materials tested were both brittle and ductile materials from the company and fought at predetermined temperatures. Under this standard, the smaller specimen the results are affected by the pendulum does not hit them in the center. Therefore made some shims (spacers) to raise up the samples so that the pendulum strikes the sample at the center. A comparison between the shim and without shims are made and how the internal friction off the machine can be checked in the smoothest and most appropriate way. The report shows how the samples are manufactured and prepared before they hit, which machines and the different grades used in this thesis. The results of battles show that there is no significant difference with or without shims for the different materials at those predetermined temperatures. Even a paired t-test is done to know whether there is any significant difference between with and without shims. The results of the paired t-tests revealed that the only one of the tests there was a significant difference between with and without the shims. The values of the internal friction shows that the internal friction does not varies much. How to control the internal friction off the machine in the smoothest and most appropriate way is to acquire a system that allows workers must turn blank firing at the beginning of each shift and then check the results and correct results are automatic. Since the centering pin used by the company today centers along the edge of the sample must test bar to be exactly 55 mm long. To get a better alignment can now acquire a centering pin that centers through the notch instead. This is mostly because the centering should not affect the measured test result. The conclusions that can be drawn from the results is that for certain temperatures it does not matter if the test pieces struck with or without shims even if there was one test that was significantly different. Since it is a tiny difference of tenths of a joule and the company reports only integers the difference does not matter. The internal friction does not vary so much that it affects the result.

  • 86.
    Bengtsson, Sebastian
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    Validering av ny laserskärande provberedningsteknik inför materialprovning2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this project is to investigate why the 0,2 % proof strength are stronger for the tensile specimens that are produced from laser cutting compare to these that are produced by manual cutting. This phenomenon is likely depending on the higher temperature that’s formed from the laser cutting. An investigation on the choice of the cutting parameters affects the temperature of the test coupon and also how the cutting order could keep the temperature low was made. The Brinell toughness for the laser cut and manual cut plates shall been compared against each other and if it’s necessary to change the size of the laser cut plates. The focus in this project is on the tensile specimens and the Brinell plates.

    The results shown that it’s a significant difference between the laser cut and manual cut tensile specimens and also that the laser cut tensile specimens has a temperature of 120 °C under the cutting process. The various settings for the cutting parameters does not results in any major difference except that a lower ultimate tensile strength, Rm, is shown at the new settings and that the tensile specimens are more likely to get stuck in the coupon. The results from the Brinell hardness tests show that there are no bigger differences between the laser and manual cut test pieces. It also shows that there are no differences between the various milling machines.

    Hardness profiles were made on already milled tensile specimens because according to earlier studies it’s shown that the HAZ disappear after milling. This result shows that it isn’t any bigger difference between the various manufacturing methods, however it’s difficult to interpret the result because the hardness value is resulting from putting the lines manually for calculating the diagonals from the impact. The result can vary with approximately ±5 kg/mm2 because the lines are added manually.

    Pictures of the microstructure was taken see if there is any changes in the structure from the cutting process and no changes in the structure can be determined from these pictures. A statistical analysis was made on all the tests to get a correctly statistical conclusion and these analyses were made in the program MINITAB. The conclusions that are made from the results are that the increase on the 0,2 % proof strength depends likely on epsilon carbides and can be minimized either through a lower or higher temperature in the tensile specimens at the cutting process or adding more Si to the material. There are no differences between the various milling machines at the milling on the Brinell plates or between the laser cut and manually cut plates. There might be some remaining HAZ after the milling on the tensile specimens, however it’s only on the upper part of the specimen.

  • 87.
    Berg, Jan
    et al.
    Luleå University of Technology.
    Wingstedt, Johnny
    Dalarna University, School of Humanities and Media Studies, Sound and Music Production. Luleå University of Technology, Sonic Studio, Interactive Institute, Piteå, Sweden.
    Perceived properties of parameterised music for interactive applications2006In: Journal of Systemics, Cybernetics and Informatics, ISSN 1690-4524, Vol. 4, no 2, p. 65-71Article in journal (Refereed)
    Abstract [en]

    Traditional implementations of sound and music in interactive contexts have their limitations. One way to overcome these and to expand the possibilities of music is to handle the music in a parameterised form. To better understand the properties of the musical parameters resulting from parameterisation, two experiments were carried out. The first experiment investigated selected parameters’ capability to change the music; the second experiment examined how the parameters can contribute to express emotions. From these experiments, it is concluded that users without musical training perform differently from musicians on some of the parameters. There is also a clear association between the parameters and the expressed basic emotions. The paper is concluded with observations on how parameterisation might be used in interactive applications.

  • 88.
    Berg, Jan
    et al.
    Luleå University of Technology.
    Wingstedt, Johnny
    Luleå University of Technology.
    Relations between musical parameters and expressed emotions: extending the potential of computer entertainment2005In: Proceedings of ACM SIGCHI International Conference on Advances in Computer Entertainment Technology ACE 2005 / [ed] S. Zhou, Z. Ying & L.S. Ping, New York: ACM Press, 2005, p. 164-171Conference paper (Refereed)
  • 89.
    Berg, Jan
    et al.
    Luleå University of Technology.
    Wingstedt, Johnny
    Luleå University of Technology.
    Liljedahl, Mats
    Lindberg, Stefan
    Perceived properties of parameterised music for interactive applications2005In: WMSCI Proceedings 2005 : July 10 - 13, 2005, Orlando, Florida, USA, 2005Conference paper (Refereed)
  • 90. Berger, Robert
    et al.
    Bexell, Ulf
    Dalarna University, School of Technology and Business Studies, Material Science.
    Grehk, Mikael
    Dalarna University, School of Technology and Business Studies, Material Science.
    Hörnström, Sven Erik
    A comparative study of the corrosion protective properties of chromium and chromium free passivation methods2007In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 202, no 2, p. 391-397Article in journal (Refereed)
    Abstract [en]

    Commercially available passivation methods for white-rust protection of hot-dip galvanized steel have been investigated. The passivations were either based on trivalent chromium or chromium free. A chromate based conversion coating was used for reference. The treated panels were tested with regard to white rust protection and paintability. The surface chemistry of the conversion coatings was monitored with scanning Auger electron spectroscopy and X-ray photoelectron spectroscopy. Coating thicknesses were measured using Auger electron sputter depth profiling. The passivations were applied with a thickness recommended by the supplier and thus showed large variation. The thickness of the chromium free passivation (Cr-free) is approximately 75 nm. The coating contains the active ions; H3O+, Ti4+, Mn2+, Zn2+, PO4 3-. The passivation based on trivalent chromium (Cr-III) is approximately 30 nm thick and contains the active ions; H3O+ Cr3+, PO4 3-, F. The chromate based passivation (Cr- VI) is approximately 5 nm thick and contains the active ions Cr6+/Cr3+, F-. The Cr-free and the Cr-III passivations showed similar white rust protection in the corrosion tests. The corrosion resistance was good although it did not fully reach the level of the Cr-VI passivation. The results from the tests of the painted panels showed that the powder paint worked well on all three passivations. The solvent born paint worked best on the passivation based on trivalent chromium. The water born paint showed poor resistance to blistering in the Cleveland humidity test for all three passivations. In this test the passivation with hexavalent chromium showed slightly better results than the chromate free passivations.

  • 91.
    Berger, Robert
    et al.
    Dalarna University, School of Technology and Business Studies, Material Science.
    Bexell, Ulf
    Dalarna University, School of Technology and Business Studies, Material Science.
    Stavlid, N.
    Grehk, Mikael
    Dalarna University, School of Technology and Business Studies, Material Science.
    The influence of alkali-degreasing on the chemical composition of hot-dip galvanized steel surfaces2006In: Surface and Interface Analysis, ISSN 0142-2421, E-ISSN 1096-9918, Vol. 38, no 7, p. 1130-1138Article in journal (Refereed)
    Abstract [en]

    The influence of dipping temperature and time on the surface chemistry of hot-dipped galvanized steel sheets during the alkaline degreasing process is investigated. The surface chemistry was monitored with scanning Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectroscopy (ToF-SIMS). The results show high Al concentrations on the untreated surfaces, which are significantly reduced during alkaline degreasing. The same conclusions could be drawn for the carbon compounds that accumulate on the surface during storage. The measurements reveal a gradual reduction in surface Al as the alkali solution temperature and/or degreasing time are increased. When degreasing was conducted at 70 °C for 30 s the surface was practically free from Al, which was present only in small islands. Furthermore, the experiments showed that the thickness of the oxide film covering the surfaces before and after alkaline degreasing is approximately 20 Å. The main constituents of the film varied from ZnAl hydroxide/oxide to Zn hydroxide/oxide, before and after degreasing, respectively. 

  • 92.
    Bergkvist, Johanna
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Strandberg, Linda
    Dalarna University, School of Technology and Business Studies, Construction.
    En pedagogisk byggnad för hållbar utveckling: Utformning av en programhandling för ett kretsloppshus med fokus på social och ekologisk hållbarhet2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to establish a functional program for an eco-cycle building where people can bereached with knowledge of sustainable development. The background to this is that the municipality ofBorlänge approved a plan program with the vision of creating a new, climate neutral district and therebybecome a precursor for sustainable construction in the region. For instance, the functional program is meantto investigate the background and the prerequisites that existed. In the municipality’s plan program, thebuilding is described to have an educational function for the district and for Borlänge; a place which focuseson practical demonstrations and education for students and residents in recycling issues for energy, waterand waste/material in a comprehensible and compelling way. The eco-cycle building is planned to beestablished near the new school, with classes from 6 to 9, to make a cooperation possible.Requests from the municipality is that the eco-cycle building can work like a hub in the new district, butalso become a new place of interest and put Borlänge on the map for sustainable construction. Sustainableconstruction includes resource management, minimized energy use and renewable energy sources, but alsothat resources like energy, waste and water circulate in an eco-cycle. Theory has been obtained fromliterature focusing on how we should build our houses and cities if we want to join and create a sustainablesociety.Part of the purpose of this thesis was to explore how to disseminate information on environmental andcircular issues in an educational way. The theoretical part of the thesis is therefore focusing on selected partsof education obtained from previous research in children and youth learning for sustainable development,since studies show that it is important that children learn about these issues early in life. Education forSustainable Development is an important prerequisite for achieving the sustainability goals set by the UNuntil 2030. Upcoming generations must learn a sustainable way of life right from the start while the existingpopulation must drastically change their lifestyle.In order to gather empiricism, interviews were held with people who have been involved in the planningwork with the new district. It turned out that there were former driving spirits who introduced the idea of theeco-cycle building, but that it doesn’t currently are the major priority in the ongoing work with the newschool and housing.Engaging the users at an early stage provides better conditions for achieving a result that is effective andsatisfying for all parties. The theory of design dialogues has therefore been studied to demonstrate theimportance of a good dialogue to quickly identify needs and develop ideas in design work.The result of the thesis, the functional program, can be seen as a draft on conceptual level with features andexpressions that can be applied to a building of this kind, and an inspiration for continued work. In thefunctional program, our interpretations form how the eco-cycle building would meet the requests andfunctions that’s been requested in the plan program, in order to benefit as much as possible in themunicipality's future work with the building.Conclusions are that there are no precursors of the eco-cycle building as a concept. Despite a large numberof sources of inspiration from various aspects, no example was found that combines all the aspects we havethe ambition to develop for this building. The eco-cycle building as a concept could play an important rolefor how to handle sustainable issues in a district or in a whole city. However, further work is required toinvestigate how the building should be run and managed, as well as more extensive studies of whichtechnical solutions to apply. Further work is also required to optimize the building for the future location,and the size of the building that are appropriate. There is a great interest in the building from variousparticipants in Borlänge, but to implement the idea of the eco-cycle building, one or more people need toembrace the project with the commitment that previously existed in the organization.

    Download full text (pdf)
    fulltext
  • 93.
    Bergkvist, Johanna
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Strandberg, Linda
    Dalarna University, School of Technology and Business Studies, Construction.
    En pedagogisk byggnad för hållbar utveckling: Utformning av en programhandling för ett kretsloppshus med fokus på social och ekologisk hållbarhet2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to establish a functional program for an eco-cycle building where people can be

    reached with knowledge of sustainable development. The background to this is that the municipality of

    Borlänge approved a plan program with the vision of creating a new, climate neutral district and thereby

    become a precursor for sustainable construction in the region. For instance, the functional program is meant

    to investigate the background and the prerequisites that existed. In the municipality’s plan program, the

    building is described to have an educational function for the district and for Borlänge; a place which focuses

    on practical demonstrations and education for students and residents in recycling issues for energy, water

    and waste/material in a comprehensible and compelling way. The eco-cycle building is planned to be

    established near the new school, with classes from 6 to 9, to make a cooperation possible.

    Requests from the municipality is that the eco-cycle building can work like a hub in the new district, but

    also become a new place of interest and put Borlänge on the map for sustainable construction. Sustainable

    construction includes resource management, minimized energy use and renewable energy sources, but also

    that resources like energy, waste and water circulate in an eco-cycle. Theory has been obtained from

    literature focusing on how we should build our houses and cities if we want to join and create a sustainable

    society.

    Part of the purpose of this thesis was to explore how to disseminate information on environmental and

    circular issues in an educational way. The theoretical part of the thesis is therefore focusing on selected parts

    of education obtained from previous research in children and youth learning for sustainable development,

    since studies show that it is important that children learn about these issues early in life. Education for

    Sustainable Development is an important prerequisite for achieving the sustainability goals set by the UN

    until 2030. Upcoming generations must learn a sustainable way of life right from the start while the existing

    population must drastically change their lifestyle.

    In order to gather empiricism, interviews were held with people who have been involved in the planning

    work with the new district. It turned out that there were former driving spirits who introduced the idea of the

    eco-cycle building, but that it doesn’t currently are the major priority in the ongoing work with the new

    school and housing.

    Engaging the users at an early stage provides better conditions for achieving a result that is effective and

    satisfying for all parties. The theory of design dialogues has therefore been studied to demonstrate the

    importance of a good dialogue to quickly identify needs and develop ideas in design work.

    The result of the thesis, the functional program, can be seen as a draft on conceptual level with features and

    expressions that can be applied to a building of this kind, and an inspiration for continued work. In the

    functional program, our interpretations form how the eco-cycle building would meet the requests and

    functions that’s been requested in the plan program, in order to benefit as much as possible in the

    municipality's future work with the building.

    Conclusions are that there are no precursors of the eco-cycle building as a concept. Despite a large number

    of sources of inspiration from various aspects, no example was found that combines all the aspects we have

    the ambition to develop for this building. The eco-cycle building as a concept could play an important role

    for how to handle sustainable issues in a district or in a whole city. However, further work is required to

    investigate how the building should be run and managed, as well as more extensive studies of which

    technical solutions to apply. Further work is also required to optimize the building for the future location,

    and the size of the building that are appropriate. There is a great interest in the building from various

    participants in Borlänge, but to implement the idea of the eco-cycle building, one or more people need to

    embrace the project with the commitment that previously existed in the organization.

    Download full text (pdf)
    fulltext
  • 94. Berglund, T.
    et al.
    Olsson, Mikael
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    High velocity compaction of high speed steel powder: possibilities and constraints2007In: Proceedings of the Euro Powder Metallurgy Congress and Exhibition, Euro PM 2007, 2007, Vol. 3, p. 21-26Conference paper (Refereed)
    Abstract [en]

    It is known that gas atomized powders as well as high alloyed metal powders are difficult to press into green bodies using conventional quasi static pressing techniques. However, the development of the high velocity compaction (HVC) technique has expanded the possibility to compact a larger spectrum of metal powders. Although the HVC technique has many similarities with conventional pressing techniques, the high energy impact makes it an interesting technique not only for the pressing of conventional metal powders to green bodies of high density but also for the pressing of "difficult to press metal powders". Today, high speed steel (HSS) is increasingly being used in different types of components. Consequently, there is an increasing interest in the near net shape manufacturing of HSS components. The aim of the present study is to evaluate the possibility to utilize HVC to press green bodies from different types of HSS powder covering both gas and water atomized HSS powders. The results show that the HSS powders investigated differ with respect to compaction properties, i.e. compressibility and green body quality. While the water atomized powders exhibit very good compaction properties, resulting in green bodies of high density, good surface finish and high strength, the gas atomized powders cannot be pressed in the as-atomized condition using HVC. However, agglomerated as well as milled gas atomized HSS powders show significant improved compaction properties compared to the as-atomized powders, although all showed defects of varying sizes depending on the applied energy during compaction.

  • 95.
    Berglund, Tomas
    et al.
    Sandvik Powder Solutions.
    Hall, Josefine
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    Wear of PM HIP Metal Matrix Composites - Influence of Carbide Type2019In: HOT ISOSTATIC PRESSING, HIP' 17 / [ed] Dayal, P Triani, G, MATERIALS RESEARCH FORUM LLC , 2019, p. 142-148Conference paper (Refereed)
    Abstract [en]

    The type of hard phase in combination with matrix material has a great influence on the wear properties of PM HIP Metal Matrix Composites. The hardness and toughness of the hard phase as well as its reaction with the matrix in combination with wear mechanism can cause significant differences in performance of the material. Three materials with the same matrix alloy but different carbide types have been studied with regards to tribological behavior in low stress and high stress abrasion as well as scratch testing against a quartz stylus. In low stress abrasion testing the materials has only very small differences in the performance between the materials. The materials containing crushed or spherical fused tungsten carbide had a higher initial wear rate compared to the material with macrocrystalline carbide. This can be explained by the higher degree of carbide dissolution in these materials. In the later stages of wear the three materials have similar performance. In the scratch testing a clear difference can be observed between the materials. The material containing the fused tungsten carbide exhibits a higher degree of carbide damage at the exit side of the wear scar sliding over the carbide. This can be attributed to the much higher degree of carbide dissolution in the fused carbide compared to the MC carbide. The results from tribology testing are discussed and compared to wear mechanisms observed in parts that have been in service in a slurry pump and a crusher.

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  • 96.
    Bergman Bruhn, Åsa
    et al.
    Dalarna University, School of Technology and Business Studies, Occupational science.
    Rydell, Alexis
    Dalarna University, School of Technology and Business Studies, Occupational science.
    Andersson, Ing-Marie
    Dalarna University, School of Technology and Business Studies, Occupational science.
    Lindahl, Cecilia
    RISE.
    Med stallet som arbetsplats: en studie om upplevelsen av attraktivt arbete på ridskolor.2019Conference paper (Refereed)
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  • 97. Bergström, Yngve
    et al.
    Granbom, Ylva
    Dalarna University, School of Technology and Business Studies, Material Science.
    Sterkenburg, Dirk
    A dislocation based theory for the deformation hardening behavior of DP steels: Impact of martensite content and ferrite grain size2010In: Journal of Metallurgy, ISSN 1687-9465Article in journal (Refereed)
    Abstract [en]

    A dislocation model, accurately describing the uniaxial plastic stress-strain behavior of dual phase (DP) steels, is proposed and the impact of martensite content and ferrite grain size in four commercially produced DP steels is analyzed. It is assumed that the plastic deformation process is localized to the ferrite. This is taken into account by introducing a non-homogeneity parameter, f(e), that specifies the volume fraction of ferrite taking active part in the plastic deformation process. It is found that the larger the martensite content the smaller the initial volume fraction of active ferrite which yields a higher initial deformation hardening rate. This explains the high energy absorbing capacity of DP steels with high volume fractions of martensite. Further, the effect of ferrite grain size strengthening in DP steels is important. The flow stress grain size sensitivity for DP steels is observed to be 7 times larger than that for single phase ferrite.

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  • 98.
    Bexell, Ulf
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    Beläggningar till högtemperaturbränsleceller2011In: Stålforskningsdagarna 2011 / [ed] Joakim Storck, Borlänge: Högskolan Dalarna , 2011, p. 89-99Conference paper (Other academic)
    Abstract [sv]

    Det finns en tro om att framtida högtemperaturbränslecellssystem kommer att ha en arbetstemperatur i intervallet 700-850°C. Vid dessa temperaturer kan man utnyttja metalliska material som bipolära plattor i en bränslecellsstack. Det har utvecklats speciella legeringar i just detta syfte men för ytterligare öka på prestandan måste dessa legeringar beläggas med lämpliga föreningar. Syftet med denna artikel är att visa att man kan förbättra olika egenskaperna av ett ferritiskt rostfritt stål genom att belägga det med lämpliga metalliska skikt.

  • 99.
    Bexell, Ulf
    et al.
    Dalarna University, School of Technology and Business Studies, Material Science.
    Berger, Robert
    Dalarna University, School of Technology and Business Studies, Material Science.
    Olsson, Mikael
    Dalarna University, School of Technology and Business Studies, Material Science.
    Grehk, Mikael
    Dalarna University, School of Technology and Business Studies, Material Science.
    Sundell, Per-Erik
    Johansson, Mats
    Bonding of vegetable oils to mercapto silane treated metal surfaces: surface engineering on the nano scale2006In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 515, no 2, p. 838-841Article in journal (Refereed)
    Abstract [en]

    In this paper the bonding of thin vegetable oil films on mercapto silane treated aluminium surfaces has been studied. The silane molecules are attached to the surface by metal–oxygen–silicon bonds. The coupling between the unsaturated bonds of the vegetable oil and the thiol functionalised surface was obtained through a photoinduced thiol-ene reaction. The surfaces were characterised by X-ray photoelectron spectroscopy (XPS). Vegetable oil contains both saturated and unsaturated carbon chains. For the reactions investigated in this study it is the unsaturated carbon chains that can react by a thiol-ene reaction and the results indicate that it is possible to attach a vegetable oil to a metal surface pre-treated with a thiol functionalised silane.

  • 100.
    Bexell, Ulf
    et al.
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    Engkvist, Josefin
    Chalmers University of Technology, Göteborg, Sweden.
    Malmberg, Per
    Chalmers University of Technology, Göteborg, Sweden.
    Comparing 69Ga+ and C60+ for ToF-SIMS sputter depth profiling in a Cr2O3 formed during oxidation of a Ce coated FeCr steel substrate2012Conference paper (Other academic)
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