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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Find a modern and quick method to determine the U value and the thermal characteristics of a building envelope using an IR camera

Thouvenel, Julie January 2012 (has links)
The overall heat transfer coefficient of a building wall, the U value, is an interesting parameter to deduce the heat loss rate through the wall. The current method to determine this U value is well known, but is requires a lot of time to be performed. In this work a new idea of methodology is presented to get an accurate idea of the U value in a really smaller time, using an IR camera. IR thermography is a non destructive method that is mainly used today to carry out qualitative observations. In this work it is used as a quantitative tool to determine the conductivity of a wall knowing the external heat transfer coefficient. The error obtained on homogeneous and heterogeneous walls are smaller than 10 %, which is accurate enough for a fast measurement. The thermal mass of the wall can also be estimated with errors between 5 and 20 %, but only if the user has a good first guess of the real value. Finally some ideas are proposed when the heat transfer coefficient is not known, leading to less reliable results. More work is necessary to transform it as a usable method in everyday life. A part of the report concerns some attempts done with a simulation of the experiment, leading to no concrete results but it is still presented as it took some time to be studied.
2

Framtidens krav på byggnaders klimatskal : – En utredning åt Sigma Civil AB

Garzon Gamboa, Alirio January 2016 (has links)
Samtidigt som kraven på energieffektivitet inom byggbranschen blir allt hårdare har klimatskalets utformning stor betydelse. Författarens uppgift är att utreda åt Sigma Civil AB hur ett verktyg som beräknar U-värden utformas samt att med hjälp av den göra en jämförande studie på yttertak och ytterväggar, med avseende på klimatskalets påfrestningar.   Andra delar som ingår i klimatskalet är grundkonstruktioner men eftersom det är ett arbete som omfattar 10 veckor avgränsas arbetet till yttertak och ytterväggar. För att arbetet skulle kunna utföras på ett bra sätt som möjligt har författaren genom litteraturstudier i form av böcker, internetbaserade sidor och olika rapporter tagit del av information som hjälpt både vid utförande av beräkningsverktyget men också vid jämförelsen av byggdelar.   Resultatet för den här studien visade att koljerntekniken på grund av sin täta struktur fungerar bäst av de takkonstruktioner som jämfördes i studien. I den analys som gjordes för väggkonstruktioner var det en yttervägg med PIR-isolering som klarade sig bäst. En av de slutsatser som jag drar av studien är att bättre isoleringsmaterial krävs för att klara framtidens krav på klimatskalet. Det andra som är viktigt att ta med sig från studien är att byggbranschen bör vara öppen för nya tekniker, som till exempel koljerntekniken och PIR-isoleringen. / While requirements increasingly become harder in the construction industry that it will be built energy efficient, buildings envelope design plays a very large part. My task is to investigate for Sigma Civil AB how a tool that calculates the U-value is formed as well as using it to make a comparative study on the roof and exterior wall, with respect for the building envelope external influences.   Another part of the building envelope is the basic designs, but because it is a work where is only 10 weeks I need to delimit to the roof and exterior walls. In order that the work could be carried out in the best possible way I did literature study in form of books, internet based pages and various reports to receive information that helped me both when I was performing the calculation tool but also doing the comparison of the building parts.   The result of this study showed that the koljern-technique because of its dense structure works best as a roof, compared to the other roofs in the study. In the analysis made for wall constructions, it was an exterior wall with PIR-insulation that worked best. One of the conclusions that I draw from this study is that better insulation needs to meet future requirements for the building envelope. The other thing that is important to take from the study is that the construction industry should be open to new technologies, such as the koljern-technique and PIR-insulation.
3

Trä- och stålreglars påverkan av värmeflödet i utfackningsväggar

Skoglund, Erika, Flemström, Max January 2012 (has links)
Inom dagens byggande i Sverige ställs allt högre krav på den värmeisolerande förmågan hos klimatskärmen i de hus som byggs. Detta ställer i sin tur högre krav på konstruktionerna och medför även ny problematik. Standardlösningar som tidigare fungerat bra byts ut mot nya, ibland obeprövade, lösningar. De hårdare kraven på energi- och fuktdimensionering innebär alltså att vikten av val av stommaterial ökar vid en projektering. Vi har här försökt ge en realistisk bild av hur valet av reglar kan påverka energi och fukttillståndet hos en byggnad med utfackningsväggar, med fokus på reglar i fält. Till undersökningen användes referensobjekt i form av ritningar som tillhandahölls av handledaren på Clarus arkitekter. Med hjälp av dessa gjordes tredimensionella energiberäkningar som visade dels att valet av material kan ha mycket stor betydelse både för energiförluster och fukttillstånd, samt att sambanden inte nödvändigtvis behöver vara enkla. Valet av reglar har mycket varierande betydelse beroende på hur väggen är uppbyggd. Genom en laboration undersöktes skillnaden mellan slitsade och oslitsade ytterväggsreglar för att ge ökad förståelse och verifiera noggrannheten av beräkningarna jämfört med en verklig vägg. Det sista visade sig svårt att uppnå, men det var tydligt att slitsarna hade mycket stor betydelse för temperaturfördelningen i en vägg. / Construction of Swedish buildings today places higher demands on the heat-insulating capacity of the building envelope in the house built. This in turn places higher demands on the structures and also creates new problems. Standard solutions that previously worked well are being replaced by new, sometimes untested, solutions. The tougher demands on energy and moisture design means that the choice of substrate material is of greater importance than before when designing buildings.Here we have tried to give a realistic view of how the choice of studs can affect energy and humidity conditions of a building with curtain walls, focusing on studs in the field. The survey used reference objects projects in the form of drawings provided by the supervisor at Clarus Architects. Using these, three-dimensional calculations were made showing firstly that the choice of material can be of great importance both for the energy and moisture, and secondly, that the relationship is not necessarily simple. The importance of the choice of studs varies depending on how the wall is built. By a laboratory experiment, the correlation between slotted and unslotted outer wall studs was examined to provide greater understanding and verifying the accuracy of the calculations compared to a real wall. The last task proved difficult to achieve, but it was clear that the studs had great significance for the temperature distribution in a wall.
4

Heat transfer tests on EPS material and massive timber wall component

Alkhado, Luqman, Boussaa, Youcef January 2018 (has links)
Timber walls are known to be an energy efficient component in the building envelope. These building elements are essential in the passive design and have been pointed out to their ability to regulate the indoor climate and reduce energy demand. Heat transfer measurements of thermal transmittance value of Iso-timber wall component have been performed with the climate chamber at three temperature differences. The influence of temperature variations on the thermal conduction of the wall were investigated. The temperature on the warm side was kept at room temperature 20 °C while the cold side temperature was decreased from 0 C to -20 C during the tests. As the temperature difference is increased, the thermal transmittance value of the timber wall component decreased slightly due to decrease in the thermal conductivity value. The effect of density and porosity on the thermal conductivity may be related to the presence of air voids and cell boundaries inside the timber wall. Results have showed that the U-value of the timber wall component decreases at higher temperature differences which indicates the higher degree of insulation of the timber wall component.
5

Energieffektivisering genom ombyggnad : Med hjälp av VIP-Energy / Energy efficiency through renovations : With VIP-Energy

Aliu, Jeton, Youkhanis, Ledia January 2013 (has links)
Detta examensarbete har genomförts i samarbete med Värmex AB där vi har haft Anders Ericsson som handledare, och Peter Hansson (Sweco) som handledare från skolan, Kungliga tekniska högskolan i Haninge. Idag är energianvändningen i flerbostadshus en stor fråga att ta itu med, och för varje byggnadsprojekt skall en energideklaration som visar mängd köpt energi göras. Vi strävar idag efter att minska energianvändningen i flerbostadshus med 50 % till 2050. I denna analys beskriver vi vilka åtgärder man kan ta an för att minska just energianvändningen i ett specifikt flerbostadshus belägen i kommunen Nacka i Stockholm. Då denna byggnad stått från år 1949 utan större underhållning har det visat sig att byggnaden står över BBRs krav gällande energianvändning (90 kWh/m2), och stor anledning är klimatskalet. Källor visar även att delar av klimatskalet så som fasad etc. bör ändras inom 30 år efter det att det byggts, vilket inte har gjorts. Vi har genom en programvara, VIP-Energy valt att utföra denna analys. Med hjälp av offentliga handlingar från stadsbyggnadskontoret så som plan – sektion – fasadritningar har vi mätt nödvändiga mått som vi knappat in i programmet. Även information som byggnadsmaterial, läge på byggnaden och uppvärmningssystem har varit nödvändiga. Jämförelse mot BBRs krav har gjorts automatiskt i programmet och det är sådan slags information vi utgått ifrån.  Då vi i denna analys valt att fokusera på klimatskal där tak, golv, väggar, fönster och dörrar ingår visar resultatet att lägre u-värden på byggnadsdelar bidrar till lägre energianvändning. Studier visar att ca 35 % av värmeförlusterna är via fönster, och detta överensstämmer med byggnaden som denna analys är baserad på. Som lösning till detta har vi valt att byta fönster till 2-glas fönster med isolleruta vilket har betydligt lägre u-värde än de vi har idag. Vi vill även förbättra karmen och fogen kring fönstren för att minska transmissionsförlusterna och eventuella drag i bostäderna, vilket i sin tur leder till bättre komfort och skönare atmosfär. Detsamma gäller yterdörrarna som behöver bytas för att hålla värmen inne. Utvändig isolering i ytterväggen bidrar även med förbättringar kring u-värde och energianvändning. Originalhuset visade att byggnadens genomsnittliga U-värde ligger på 0,656W/m2K och energianvändningen ligger på 96 kWh/m2 per år. Enligt BBRs krav för äldre byggnader ska u-värdet ligga på 0,400W/m2K och energianvändningen på 90kWh/m2 per år. Energibalansberäkningen visar nya värden på byggnaden, vilket är totala u-värde på 0,409 W/m2K samt energianvändningen på 64 kWh/m2. / This degree project has been written in collaboration with Värmex AB, with the generous help of Anders Ericsson as our fellow adviser and Peter Hansson (Sweco) our mentor from the Royal institute of technology located in Haninge.   Today we find questions pertaining to energy consumption in apartment blocks of real significance; with each building project a declaration that shows the amount of energy consumed is of outmost importance. We strive to reduce energy consumption in apartment blocks by 50 % until year 2050. In this degree thesis, we aim to describe measures and solutions to lower the consumption of energy in a specific apartment block located in Nacka, Stockholm.   This building has been standing quite untouched and unmarked since 1949, yet it is still in compliance with the demands stated by BBR concerning energy efficiency, in large because of its climate shell. Sources show that greater parts of its outer shell for example the front, should have been repaired during the first 30 years, and the matter is still to be solved. The use of a computer software VIP-Energy has enabled us to state a hypothesis. With the help of public documents from Housing And Urban Development Town Building Office (HUD) giving us an overview of the different dimensions of the building, we've been able to plot all this data into the software. Information such as building materials, location, heating systems have also been necessary in our analysis. Results are automatically compared to the demands required by BBR. It is through experimentation of this data that we have been successful in collecting our results.  In the analysis, we chose to focus on the climate shell that constitutes: roof, floors, walls, windows and doors. Our results show that lower U-values conduce better energy efficiency. Studies show that almost 35 % of energy loss in a building is caused by the windows of the building, this this is consistent with the building which this analysis is based on. We have solved this by changing sheet glass that is energy efficient. We also aim to change the frame and seams surrounding the windows, in order to lower transmission losses and possible draughts in the apartments. This will result in hopefully a higher degree of comfort and refreshing atmosphere. The same changes apply to entry doors in order to keep energy loss to a minimum. Also an external insulation in the outer wall contributes to improvements on u-value and use.  The original building shows an average U-value of 0,656W/m2K and the energy consumption is 96 kWh/m2 per year. According to BBR, older buildings should have a U-value of 0,400W/m2K and an energy consumption of 90kWh/m2 per year. Energy balance calculation show new values for the building were the u -value should be set to 0,409W/m2K, and energy consumption should be set to 64kWh/m2.
6

Isolering av fraktcontainers yttervägg / Insulation of the outer wall of the shipping container

Ibrahim, Alan January 2022 (has links)
Bostadsbristen i Sverige påverkar 75% av alla kommuner. För att kunna lösa krisen snabbt och effektivt bör byggbranschen ta nya idéer och byggteknik på allvar. Att bygga bostäder av fraktcontainer innebär att bygga snabbt och miljövänligt.Denna typ av projekt behöver utveckla för att anpassa det till det svenska hårda vädret och uppfylla kraven som ställs av boverket BBR. Isolering av en containeryttervägg anses som ett problem när det gäller denna typ av projekt. För att flera ska bygga bostäder av fraktcontainer behöver problemet att lösa. Genom att samla in information och ta inblick i redan byggda bostäder av fraktcontainer ska två olika alternativ för ytterväggars isolering jämföras. Risk för köldbryggor, U-värde och kostnad ska jämföras. / In Sweden, 75% of municipalities are affected by a shortage of housing. To solve the housing crisis, the construction industry must adopt effective and innovative construction techniques and methods. By building housing out of shipping containers, the result will be fast, environmentally friendly, and costeffective. However, this type of housing needs a building technique developed and adjusted for the harsh Swedish climate and fulfill the National Board of Housing, Building, and Planning requirements. One significant problem hindering the process of this project is isolating the container’s exterior wall. Solving this problem will encourage the construction industry to build this type of housing. Through data collection and considering shipping container housing built already, this paper will make a comparison between two different options for wall insulation will be compared. Further the U- value, costand thermal bridges risk will be compared.
7

VÄRMEGENOMGÅNGSTALETS UTVECKLING : Progress of the heat transfer coefficient

Kruszewski, Tomasz, Olsson, Anna January 2023 (has links)
År 1947 var k-värde, värmegenomgångstal, aktuellt och Sverige var indelat i olika zoner med lokala byggregler. Sedan dess har bygglagstiftningens utveckling gått framåt. Lagen har förändrats och många nya föreskrifter och anvisningar har utgivits under årens gång. Det förekommer inte längre några zoner eller lokala byggregler. I dag är begreppenvärmegenomgångskoefficient (Um) och byggnadens primärenergital (EPpet) aktuella.Denna rapport innehåller en sammanställning över tillåtna värden för värmegenomgångstalet och hur det utvecklats från 1947 fram till i dag. Rapportens syfte är att skapa en förenklad sammanställning över hur värmegenomgångstalet förändrats historiskt med hänsyn till bygglagstiftning. En översikt för antalet småhus och flerbostadshus är också inkluderad. Sammanställningar över dessa värden fyller en viktig funktion i förarbetet till Fit for 55 och är betydelsefullt för övriga kommande miljöarbeten. Litteraturstudien har utgått från regelverken BABS, SBN, NR, och BBR. Statistiken för antalet bostäder är hämtad från SCB.Arbetet omfattar byggregler från BABS 46 fram till BBR 29 och inkluderar endast byggnadsdelarna golv, vägg och tak. Sammanställning för värmegenomgångstalets utveckling är begränsad till bostad. Resultatet redovisas i tabeller och diagram. Sammanställningen gav en tydligare bild av hur värmegenomgångstalet har förändrats och var förändringen var som störst.  Syftet var att sammanställa en förenklad version av värmegenomgångstalets (k-värdets) utveckling genom historien, vilket är uppnått. / By 1947, k-value, was the standard value and Sweden was divided into different zones with local building regulations. Since then, the progress of the building legislation has been moving forward. The law has changed, and many new regulations and instructions have been published during the years. There are no longer any zones or local regulations. Today, the current concepts are U-value and EPpet. This report includes a compilation of allowed values for k-value and how it has been developing since 1947 until today. The purpose of the report is to create a simplified compilation of how k-value has been developing historically regarding building legislation. An overview of the numbers of small houses and apartment buildings are also included. Compilations of this type of values are an important part in the preparatory work to Fit for 55 and are also valuable for upcoming environmental work. The literature study has been done from the regulations BABS, SBN, NR and BBR. The statistics of the numbers of homes has been collected from the SCB. The work covers building regulations from BABS 46 until BBR 29 and only includes the building parts floor, wall, and roof. The compilation of the development of k-value is limited to residences.The outcome/result is reported in charts and graphs. The compilation gave a clearer picture of how k-value has developed and where the biggest changes occurred. The purpose was to compile a simplified version of the k-values development throughout history, a purpose which was achieved.
8

How bright does the sun shine over Storvreta IK? : Mapping the energy use of a local Swedish sports club

Dahmén, Viktor, Holgersson, Martin, Larsson, Aron, Norman, Joel January 2016 (has links)
In 2011 Storvreta IK installed two solar collector systems in order to reduce the club’s electricity demand for domestic hot water. However, electricity use from 2012 to 2015 shows that the expected reduction in the electricity demand has not occurred. This project investigates the solar collector systems and the heat demand of Storvreta IK’s buildings in order to explain the “failure” in electricity savings. The results of the simulations show that the heat production of the solar collectors is lower than Storvreta IK’s expectations. This could be explained by that the domestic hot water is not used as much as Storvreta IK thought and the system is therefore over-dimensioned for their need. The rebound effect could be another reason to why the electricity saving is lower than expected.
9

Energy Audit and Energy Saving Measures of a Large Office Building : Bern 9 in Örnsköldsvik

Björklund, Lina January 2020 (has links)
There is a large potential in making the residential and service sector more energy efficient and the first step towards achieving a more efficient use of energy is to implement an energy audit. In this study a property with an approximate area of 8 000 m2, consisting of a main building and three building extensions from different eras has been examined. The main building and its extensions were built in different stages and the first one in the early 20th century and some parts of the last building extension were modified at the time that the examination was carried out. This indicates that there is a vast energy savings potential in the property and an energy audit was performed. The main aim of the study was to examine where the energy was being used and where energy could be saved. Energy saving measures has been suggested together with a calculated approximate energy decrease and payback period. The total energy savings potential for the measures is approximately 146 MWh. The energy audit showed that a large amount of electricity was being used during non-work hours and that energy was lost through the building envelope. The electricity use during non-work hours was examined during the night walk, however, it is suggested to carry out further examinations regarding the property’s vast electricity use during non-work hours. To add loose wool in the roof of B2 has an energy savings potential of 33 000 kWh/year. Another measure is to clean the heat exchangers, this measure has an energy savings potential of 26 000 kWh/year. Also it is suggested to optimize the operational hours for the lighting by implementing presence control and to decrease the energy use for ventilation by cleaning the heat exchangers. Further examinations that would improve the study would be to do measurements of the electricity and temperatures to get a better understanding of the buildings energy use. Also to model the building in a simulation tool would give a calculated energy loss that is more like the actual energy loss of the building and make the results more reliable.
10

Optimering av klassrumsmiljön i en ny skolbyggnad i Västerås : En studie om fönsterplacering och energiförluster

Fadi, Kunda, Nahla, Alhamada, Mert, Celen January 2023 (has links)
Purpose: The purpose of this study was to plan blueprints for a school located Härbregatan and Vallby Skolgata in Västerås with a focus on energy losses and window placement to choose the most suitable types of windows to obtain a good internal environment. Method: The methodology used to conduct this thesis was based on earlier case studies, literature book and literature reviews in the form of legal specification from Boverket Byggregel (BBR) that had a significant impact on how the school was designed, interior and exterior views. Results: The study demonstrated how important window types and selection was for the students and the teachers occupying the classrooms because windows are a vital source of light, energy and encouragement due to the daylight. Larger windows minimize the need for electrical lighting but increases the risk of energy loss due to inadequate insulation resulting in an impact on the indoor environment and causing a higher energy usage. The size of the window also has an impact on specific transmission losses, thermal bridges, heat losses and as well as the solar radiation passing through the glass, according to this study. Conclusions: The study came to the conclusion that while windows have a significant role in these aspects, additional aspects that include the size of walls, doors, floors and ceiling also play an essential part. Larger windows lead to increased transmission losses and thermal bridges, but at the same time it lets in more daylight and sunlight in the form of heat energy, therefore larger windows are a better choice to use in the school building.

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