Miljo och energi ar tva faktorer som blir allt viktigare, och energisnala hus har nu funnits en tid pa marknaden. Att ta lagenergihus ett steg langre, och gora plusenergihus som levererar mer energi an vad den gor av med, ar inte lika val testat i Sverige annu. Da tjockleken pa vaggarna blir storre ar det ocksa viktigare att hitta tekniker som minskar koldbryggor vid anslutningar. For att forsta hur man pa basta satt ska utforma och konstruera dessa hus behovs kunskap om material, koldbryggor, byggnadsdetaljer, klimat och uppvarmningssystem. Bland annat har en analys av vilka olika varmesystem som passar bra for ett lag-/plusenergihus gjorts i denna examensrapport, med stod av referensobjekt. For att huset i framtiden ska kunna utnyttjas som ett plusenergihus behovs ett system som har kapacitet att lagra energi under en kortare tid. Istallet for att anvanda bergvarme gar det exempelvis att installera solfangare, som aven fungerar bra i Sverige, och vintertid racker det med en braskamin. I samarbete med Trivselhus har generella principer for koldbryggor tagits fram genom berakningar for hand och i programmet UNorm version 2011:1. Resultatet visar att det kritiska omradet vid anslutningen platta pa mark och vagg ar syllen, och det ar viktigt att dessa anslutningar blir sa tata som mojligt. For att minska varmeflodet i detta kritiska omrade ar det en fordel att dela syllarna och att isolera emellan dem. For koldbryggor kring fonster har resultaten fran berakningar, bade for hand och genom Unorm, visat att koldbryggorna ar storre i en tjock vagg. I en tjock vagg ar varmeflodet trogare och vaggen upplevs som kall. Detta har inte sa stor inverkan pa sjalva innetemperaturen, men vaggen far ett mildare uttryck. En solstudie i Revit Architecture har utforts dar fonstren forst har placerats i ytterkant pa fasad och sedan i innerkant for att undersoka vilken skillnad det gor i solinstralning och transmissioner fran och till byggnaden. Nar fonstren placeras i innerkant bildar vaggen en sollada och skuggar fonstret mer an om det ligger i fasad. Utifran det har resultatet ser man att det spelar en stor roll var man placerar sina fonster. Sommartid forloras en hel del solenergi om man placerar fonstren i innerkant av fasad, istallet for i ytterkant. En hel del gratisenergi kan utvinnas om man placerar fonstren i ytterkant av fasaden. Skillnaden i solinstralning for de olika placeringarna motsvarar nastan en femtedel utav en villas totala arsforbrukning. / Environment and energy are two factors that have become more important as the development in general is increasing over the world. Low-energy houses have been on the market for a while now, and the development of buildings is moving towards houses that can produce energy both to deliver and to supply the house itself. As the thickness of the walls increases it becomes more important to reduce the thermal bridges among construction details, for example connection between wall and slab. To understand how to design and construct these buildings, knowledge about material, thermal bridges, building details, climate and heating systems is required. In this thesis, analyzes have been done that concerns heating systems that are suitable for a low energy house with help from references to similar projects. Together with the Swedish company Trivselhus general principles for thermal bridges have been developed, these principles are based on calculations by hand and by using software called UNorm 2011-1. The result shows a critical part among the connection between the concrete slab and the wall. Also the joist is really important to make sure it is dense. To reduce the heat flow in this critical area, it makes sense to separate the joists and insulate between them. For thermal bridges around the windows, the results of calculations, both by hand and by UNorm, showed that thermal bridges are greater in a thick wall. In a thick wall the heat flow is slower and the wall is perceived as cold. This has not much effect on the actual indoor temperature, but the wall may get a milder impression. In Autodesk’s Revit Architecture a sun study has been created to see if there is any difference between having the windows placed in the facade or in the inner part of the facade. Will it make any difference for the shading of the window and how will it affect the sun insolation and the transmission of energy in and out of the window? When the window is further into the wall, the wall creates a box that increases the shading of the window. Based on this result you can see that the placing of the windows does matter. During the summertime a lot of solar energy will be lost if the window is placed further in to the facade. The transmission from the building, through the windows, is not that big, but the greatest difference can be seen in the total solar insolation. A lot of energy can be extracted from the sun insolation, if you place the windows right, which is in the outside of the facade. Almost one fourth of a buildings total energy consumption of a year can be received from the solar energy only through the windows, if they are placed in the outside of the facade.

Some of the problems with today’s urban civilizations are the lack of green areas and that the cities are getting warmer and warmer. Building green roofs contributes to a reduced greenhouse effect, as plants have a cooling effect that reduces the heat generated in both houses and cities. The greenhouse effect is reduced by the fact that the plants on the roof reflect much more solar energy than a black ceiling, which instead absorbs the heat. The plants help to make the building more energy efficient. Green roofs also contribute to the emergence of new green areas in cities where the settlement has taken over the city. The purpose of the study has been to, from an energy perspective, examine the advantages and potential disadvantages of green roof energy performance in the subarctic climate. The study has been conducted by analyzing measured heat flow and temperature conditions during a winter season. The study was delimited to the green roof of Sjunde Huset in Kiruna, Norrbotten, Sweden. The research questions examined are the advantages and disadvantages of energy performance for green roofs, how does the energy performance vary for green roofs in cold climate during the season and what energy performance has the green roof under investigation in the subarctic climate. The study has been done through analysis of measurement data to see if the cooling effect from an energy perspective can be a disadvantage in a so-called subarctic climate. The analysis has also investigated whether the heat-insulating and heat-storing effect can be an advantage from an energy perspective in a so-called subarctic climate. The test period under review is from October 25, 2016 to January 4, 2017. The test period shows changes at different times. These times have been explored more closely. Collected measurement data has been analyzed using Excel chart against data for different weather conditions from SMHI. The different weather conditions are solar time, global radiation, wind speed and wind direction. Parameters that are also taken into account are polar night, night radiation, night cooling and snow conditions. The results show that green roofs are more beneficial in the subarctic climate from an energy perspective compared to black roofs. The green roof has lower temperature changes and heat flow than a traditional black roof. The internal temperature and heat flow of the green roof remain stable with minor changes during the winter period that is studied. The green roof has less temperature changes, heat flow and more stable indoor temperature than the black roof can depend, inter alia, on the thermal mass of the roof and the insulating capacity of the soil layer, which provides better thermal insulation. High wind velocities and low outdoor air temperatures can also be contributing factors to a cooling that causes slight changes in heat flow. Since the snow layer can function as an extra insulating layer and the test period only lasted until January 4, it would be interesting to see further studies where the entire winter season is analyzed. This is to see how the green roof behaves during a whole winter season, but also in the spring when large amounts of melt water can contribute to condensation that can affect heat flow. In the spring, large temperature differences can occur during day and night times that can affect heat flow through the green roof.

This study has examined how an oil storage could be converted into a thermal heat storage (TES). Focus was put on the transient thermal heat flow that occurs during the early years when using a rock cavern as a TES. First existing literature were studied to learn from earlier experiences. Crucial steps of a conversion were identified as well as important mistakes that have been made in the past. Simulations of Sundsvall’s district heating (DH) system were made to see what impact a large TES would have. These simulations showed the importance of being able to transfer enough amount of heat. Then heat simulations were preformed to study the transient heat flow. This showed that much of the heat will be heating the rock around the cavern. Over time, the losses decrease as the rock around the cavern remains heated, due to its thermal inertia. This means that some energy needs to be considered an investment cost as it will not be used in the DH-grid but will increase the efficiency of the TES. 4 different heating strategies were analysed and the heat losses during 25 years were measured. The results showed that a conversion would save between 0,7 – 1,55 million SEK annually depending on how many caverns were converted and cost approximately 6 million SEK for one cavern, 10,5 million SEK for two caverns and 15 million SEK for three caverns. / I denna studie har det undersökts hur ett oljelager kan omvandlas till ett termisk värmelager. Fokus låg på det transienta värmeflödet som inträffar under de första åren när ett bergrum används som värmelager. Först studerades litteratur för att lära av tidigare erfarenheter. Avgörande steg för en konvertering identifierades liksom viktiga misstag som har gjorts tidigare. Simuleringar av Sundsvalls fjärrvärmesystem gjordes för att se vilken påverkan ett stort värmelager skulle ha. Dessa simuleringar visade vikten av att kunna överföra tillräcklig mängd värme. Därefter genomfördes värmesimuleringar för att studera det transienta värmeflödet. Detta visade att mycket av värmen kommer att värma berget runt bergrummet. Med tiden minskar förlusterna när berget runt rummet förblir uppvärmd på grund av dess termiska tröghet. Detta innebär att en del energi måste betraktas som en investeringskostnad eftersom den inte kommer att användas i fjärrvärmesystemet utan kommer att öka effektiviteten hos lagret. Fyra olika uppvärmningsstrategier analyserades och värmeförlusterna under 25 år mättes. Resultaten visade att en omvandling skulle spara mellan 0,7 - 1,55 miljoner SEK årligen med en trivial driftstrategi beroende på hur många bergrum som konverterades och kosta cirka 6 miljoner SEK för ett bergrum, 10,5 miljoner SEK för två bergrum och 15 miljoner SEK för tre bergrum. I framtida studier bör en optimal driftstrategi tas fram utifrån det aktuella systemet.

I dagens samhälle ligger stort fokus på att bygga miljövänliga och energieffektiva byggnader. För att möta de allt mer skärpta energikraven måste hela klimatskalet beaktas där köldbryggor utgör en betydande del. Examensarbetet går ut på att göra en sammanställning av linjära köldbryggor (ψ) för vanligt förekommande konstruktionsdetaljer där köldbryggor finns. Sammanställningen där olika isoleringsmaterial på fasadskiva och isolertjocklekar tabelleras, ska underlätta för framtida projektering. Två simuleringsprogram för beräkning av köldbryggor har jämförts och utvärderats med varandra. Utvärderingen har gjorts med avseende på vilket program som var mest lämpat för att lösa frågeställningen. De två simuleringsprogrammen som används vid detta arbete är HEAT2 och COMSOL Multiphysics. Arbetet har resulterat i en lathund som finns tillgänglig på ELU:s intranät. Lathunden innehåller U-värde och ψ-värde med illustrering av konstruktionsdetaljerna och i detta arbete redovisas tillvägagångssätt och utförandet. En utvärdering av det lämpligaste program för utförandet av uppgiften finns också redovisad. / Currently there is a lot of focus on environmentally friendly and energy efficient buildings in our society. To face the more toughen energy requirements, the entire climate shell of the building has to be considered there thermal bridges constitute a significant part. This bachelor dissertation intends to create a compilation for Ψ-values of common construction details where thermal bridges are to be found. The compilation with a chart that includes insulating material and insulation thickness shall simplify in future projecting. Furthermore, two simulating programs for calculations of thermal bridges have been compared with each other. The two simulation programs that have been used in this dissertation are HEAT2 and COMSOL Multiphysics. This dissertation has resulted in a quick reference guide which is available at ELU`s internal network. This quick reference guide includes U-values and Ψ-values with an illustration of every construction detail and the procedure and execution is reported in this dissertation. An evaluation of which of the two programs that has been used was more appropriate for this purpose is presented as well.

Gearboxes are always subject of study in order to increase their efficiency. Energy losses in gear contacts are transformed into heat which is distributed among the gearbox components increasing their temperature. A thermal model of the gearbox brings the opportunity of a deeper understanding of the heat dissipated related to the power losses in the gear contact. A MATLAB program based on ordinary differential equations was developed in order to make a thermal model of an FZG test gearbox. The model is based on a thermal network where each node represents a machine element. The thermal network is composed by thermal resistances due to deformation in the gear contact, conduction, convection and radiation. With thermal resistances, power losses and thermal inertia of each element, the temperature evolution was obtained by applying the First Principle of Thermodynamics. Due to the temperature evolution, heat transfer between different elements was estimated. Additionally, experimental results from an FZG test rig were implemented in the model and also used to verify its accuracy. Furthermore, additional features to the model such as a cooling system and spray lubrication were also studied. Results show a wide capability and handling of the program in terms of thermal analysis: heat flux direction and magnitude, visual tools such as thermal network of the test gearbox, as well as the analysis of different operating conditions. With these tools, an approach to the minimum amount of lubricant necessary and other ways to quench overheating could then be reached. Keywords: Thermal network, FZG gear test rig, heat flow, temperature, MATLAB, ODE. / Växellådor är ständigt ett forskningsområde för att förbättra deras verkningsgrad. Energiförluster i kuggkontakter omvandlas till värme som sprids i växellådan som sedan värmer upp komponenterna. En termisk modell av växellådan gör det möjligt för djupare förståelse hur värmen sprids i förhållande till energiförlusterna i kuggkontakten. Ett MATLAB-program baserat på ordinära differential-ekvationer utvecklades för att göra en termisk modell av en växellåda i en kuggrigg från FZG. Modellen är baserad på ett termiskt nätverk där varje nod representerar en maskinkomponent. Det termiska nätverket består av resistanser som uppstår på grund av deformation i kuggkontakten, ledning, konvektion och strålning. Med termiska resistanser, energiförluster, termisk tröghet från komponenterna och genom att applicera termodynamikens första grundsats kunde temperatur-genereringen bestämmas. Från temperatur-genereringen kunde värme-ledningen mellan komponenter uppskattas. Testresultat från en FZG-kuggrigg användes för att verifiera modellens noggrannhet. Andra egenskaper till modellen, som ett annat kylsystem och spraysmörjning studerades för att undersöka möjligheteten att adderas till modellen. Resultat visar på en bred användning av modellen i avseende på termisk analys: värmeflödets storlek och riktning, ett visuellt redskap för växellådans temperatur och hur växellådans temperatur varierar under olika driftförhållanden. Med de här redskapen kan den minsta oljemängden som behövs för att smörja kuggkontakten undersökas och hur kylning av kugghjulen kan förbättras. Nyckelord: Termiskt nätverk, FZG kugghjuls-rigg, värmeflöde, temperatur, MATLAB, ODE

För att verifiera att komponenter håller under en förväntad livslängd kan en Accelererad Livstids Testning (ALT) användas. En av huvudaspekterna som kan förstöra ett ALT-test av plastkomponenter är om kontakttemperaturen överstiger glasövergångstemperaturen. Detta eftersom det förändrar testkomponentens materialegenskaper. För att förhindra att detta inträffar i en ALT byggdes en testrigg medtemperatursensorer för att övervaka kontakttemperaturen. Om kontaktpunkten modifieras med en temperatursensor förändrar det uppbyggnaden av ytan och gör testet ogiltigt. Metoden som används är istället att mäta temperaturen på ytan på testdelen och simulera kontakttemperaturen med en modell baserad på den Finita Elementmetoden. Denna avhandling jämför de två teknikerna Tunn Film RTD och Tunn Termoelement Tråd Typ T i samband med uppbyggnaden av en värmeöverföring FEM-modell. Det undersöktes också vilken teknologi av IR-enpunkts sensor och Tunn Film RTD som har högst prestanda med avseende på fyra kvalitetsparametrar under användning tillsammans med testriggen. Slutsatserna är att Tunn Film RTD och Tunn Termoelement Tråd av Typ T sensorerna båda ger en liknande precision i mätningar för att bygga en användbar FEM-modell. När de används på testriggen presterar Film RTD:n är bättre än IR-sensorn i tre av fyra områden med avseende på de fyra definierade kvalitetsparametrarna. Tunn Film RTD är den rekommenderade teknologin för denna typ av mätning. / To verify that components last for an expected lifetime an Accelerated Life Testing (ALT) can be used. One of the main aspects that can ruin an ALT of plastic components is if the contact temperature rises above the glass transition temperature, since this changes the material properties of the tested component. To prevent this from occurring in a ALT, a test rig was built with temperature sensors to monitor this contact temperature. If the contact point is modified with a temperature sensor, this will change the surface and make the test invalid. The method is instead to couple surface temperature measurements with a Finite Element Model (FEM) to estimate the contact temperature. This thesis compares the two techniques Thin Film RTD and Thin Thermocouple Wire Type T in conjunction with the building of a heat transfer Finite Element Method (FEM)-model. It also investigates which technology of Non Contact IR Single Point sensor or Thin Film RTD have the highest performance in use with the test rig with regard to four quality parameters. The conclusions are that RTD and the Thermocouple Type T sensors both provide equal precision in measurement to build a useful FEM model. In application on the test rig, the Thin Film RTD is better than the Infrared (IR)-sensor in three out of four areas when compared in the four defined quality parameters. Thin Film RTD is the recommended technology in this application.

The Phase change materials (PCM) have the ability to absorb and release heat as the temperature changes from high to low temperature and vice versa. The use of phase change materials has increased in the construction sector due to the established environmental requirements and the various application benefits, especially in the thermal comfort of building applications and construction of sustainable infrastructure around the world (Berardi and Gallardo, 2019). Over the past decade, many studies have been conducted on the thermal properties of PCM (phase change material), however, few studies have focused on the study effect of PCM on mechanical and physical properties, although of great importance. In this work, three different microencapsulated types of phase change material (PCM) have been studied, while its effect on the mechanical and hydration properties of the cement paste with regard to constant ratio of water to cement ratio has been taken into account. The PCMs that have been studied are the following: Microencapsulated PCM, which is Nextek 24 D, Nextek 57D (Microtek Laboratories) and Croda Therm ME29P (Croda). In this study, various tests were performed on cementitious paste mixed with different doses of PCM to test the effect that PCM has on the cement hydration (under semi-adiabatic and isothermal conditions), the physical properties (setting time, slump flow, density) and the mechanical properties ( compressive strength). The results of this study indicated that both the melting point of the PCM and its amount have a decisive effect on the properties of the cement paste. Finally, the following conclusions have been drawn: • Additions of different dosage levels of the 24D and Croda PCM types showed that an increase in the dosage resulted in impaired mechanical and physical properties such as compressive strength of the cement paste (mechanical) decreased, and the density and random flow decreased (physical). While Nextek 57D did not show a great effect on cement paste according to density and random flow, which gives reduced negative impact on cement paste workability (physical). According to the mechanical properties, Nextek57D PCM with different levels of levels showed immediate positive effect on cement paste compressive strength compared to reference paste (no addition of PCM), and other cement pastes with other PCM types used in this study. • Mikrotek 57D PCM also gives a positive effect at different dose levels compared to two other types of Nextek 24D and Croda PCM regarding the effect of heat flow, which gives rise to hydration heat during the cement hydration process. However, other types of Nextek 24D and Croda in all quantities showed negligible effect on the heat flow during the cement hydration process.

HotHumiBox är en försöksutrustning som finns på Linnéuniversitetet och som ska ge bättre kunskap och förståelse om hur fukt och temperatur varierar i en provkropp monterad mellan två kammare där klimatet kan styras var för sig. Syftet med examensarbetet är att undersöka om HotHumiBoxen fungerar väl och huruvida den kan börja användas i undervisningen i olika kurser inom institutionen för byggteknik på Linnéuniversitetet, bl.a. i samband med demonstrationslaborationer vid föreläsningar om fukt. För att genomföra arbetet har mätningar med tre olika klimat utförts på ett provelement som motsvarar en yttervägg som kan finnas i nybyggda typhus. Resultatet av mätningar utförda med HotHumiBoxen presenteras i form av tabeller och diagram och jämförs slutligen med beräkningar av fukt- och temperaturtillstånd. Jämförelsen mellan mätningar och beräkningar visar att givarna som styr klimatet i båda kamrarna visar mycket bra resultat. Däremot visar majoriteten av givarna i provelementet antingen lite för höga eller för låga värden för att resultatet ska anses som tillfredställande. För att få en bekräftelse på att HotHumiBoxen fungerar väl rekommenderas därför att ytterligare mätningar görs. / HotHumiBox is an experimental equipment that is available at Linnaeus University and is supposed to provide better knowledge and understanding about the way moisture and temperature varies in a building element installed between two chambers in which the climate can be controlled separately. The purpose of this work is to investigate whether the HotHumiBox works well and whether it can be used at various courses at the Department of Building Technology at Linnaeus University, such as demonstration laboratory experiments at lectures on moisture. Measurements with three different climates were performed on a building element that corresponds to a wall that could be installed in modern houses. The results of the HotHumiBox measurements are being presented in tables and diagrams and are being compared with moisture and temperature calculations. The comparison between measurements and calculations shows that the sensors which control the climate in both chambers show very good results. On the other hand, the majority of the sensors in the test element show either too high or too low values for the result to be considered as satisfactory. Therefore, it is recommended that some more tests and measurements are done before it can be concluded that the HotHumiBox work well.