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<em>Isolerande balkonginfästningar</em> : Thermally-insulated balconiesKulasin, Aid January 2009 (has links)
<p>In this work a study has been performed to show the different kinds of insulated balcony connections exists on the market. In the work there is also a short description of thermal bridges concerning balconies. A description of older solutions for balcony connections is given as well as a calculation of the difference in energy costs for a insulated balcony connection compared to the standard connection. The work includes a short description of the different products. After that there is a short information about their insulation properties, durability, acoustic performance, assembly, computer programme and a short analyses for each product.</p>
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Isolerande balkonginfästningar : Thermally-insulated balconiesKulasin, Aid January 2009 (has links)
In this work a study has been performed to show the different kinds of insulated balcony connections exists on the market. In the work there is also a short description of thermal bridges concerning balconies. A description of older solutions for balcony connections is given as well as a calculation of the difference in energy costs for a insulated balcony connection compared to the standard connection. The work includes a short description of the different products. After that there is a short information about their insulation properties, durability, acoustic performance, assembly, computer programme and a short analyses for each product.
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Vacuum insulation in buildings : means to prolog service lifeThorsell, Thomas I. January 2006 (has links)
<p>Vacuum insulation panels, VIPs, constitute a new insulation material, 6 to 8 times better than traditional insulation materials, which utilizes the positive influence vacuum has on the thermal properties of certain materials. A VIP is a composite with a flat core enclosed by an envelope preventing the core to fill with gas. The vacuum in the core is vital to reach thermal conductivities down to 0,0035 W/(m K), if the vacuum is lost the panel has reached the end of its service life time. Metal sheets would the preferred material to create an impermeable envelope but would creates a large thermal bridge at the edges of a panel when it folds over the edges of the panel.</p><p>A serpentine edge has been proposed in order to deal with this large thermal bridge. This serpentine edge has been evaluated first as a numeric model in software and then by measuring on a prototype edge element in a hot and cold plate instrument. Measured temperatures were used to validate the numerical model. Results show that a serpentine edge can greatly reduce the thermal bridge if designed correctly.</p><p>Another direction taken in the development of the VIP barrier is to use very thin metal layers, metallization layer or coating, incorporated into multi layered polymer composite film. This creates barrier films with very good barrier properties and only small thermal bridges. The modeling of gas flux through films with more than one coating has only just started. Existing models for flux through multi coated films all assume that flux is only taking place through defects in the coating layers, that all defects are of the same size and that all defects are positioned in square lattices. The model discussed herein use the same assumption of flux through pinholes only but it does take defect sizes and positions into account. Barrier film, from a regular vacuum insulation panel, with double coatings has been evaluated in light microscopy to characterize the defects in each of the coatings. The data found have been fed into the model and the results comply well with reported permeabilities of similar barrier films.</p>
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Contribution à l'économie d'énergie dans le bâtiment : mesure de capacité de stockage dynamique d'une paroiProdjinonto, Vincent 15 December 2011 (has links)
L’économie d’énergie dans le bâtiment est devenue une question préoccupante d’envergure internationale. Le secteur du bâtiment en effet, est l’un des plus énergétivores avec par exemple plus de 43% du total d’énergie produite en France, mais aussi l’un des plus polluants avec environs, 23% des émissions de gaz à effet de serre. Avec l’accroissement des ménages, et la demande par conséquent d’énergie, les problèmes ci-dessus évoqués vont décupler et devenir rapidement ingérables les années à venir, si aucune mesure n’est prise. Ainsi, pour faire face à la situation, plusieurs stratégies sont mises en œuvre aux fins de réaliser l’économie d’énergie dans le bâtiment. Il y a le volet prédiction d’énergie qui oeuvre pour l’énergie juste heure après heure ; le volet recherche et élimination de ponts thermiques, afin de réduire au minimum les déperditions d’énergie représentant environ 30% de la consommation d’énergie ; et le volet conservation d’énergie dans les parois de bâtiment pour sa réutilisation future. Notre thèse s’est penchée sur les deux derniers volets en proposant différentes méthodes de CND et des traitements appropriés permettant la mise en évidence de défauts dans les structures de bâtiment. Des approches d’estimation de matrice de transfert ont été aussi abordées, pour permettre de prévoir le comportement thermique du bâtiment soumis à une sollicitation quelconque. La grande contribution de cette thèse concerne la mise au point d’une technique de mesure de capacité de stockage in-situ. Elle est importante, car il existe quantité de logiciels proposant la composition des structures d’un bâtiment pour une capacité de stockage d’énergie donnée. Mais il n’existe aucune méthode permettant de confirmer ou d’infirmer les résultats issus de calculs artificiels. Cette thèse apporte une solution à cette situation en proposant une méthode simple, sans encombrement, facile à mettre en œuvre et offrant un résultat satisfaisant. / Energy saving in buildings has become a major international issue. Indeed, the building sector is one the most energy consuming sectors, for instance in France it consumes more than 43% of the total produced energy, and also it is one of the most polluter with around 23% of the green house gas emissions. As more and more households appear, the energy demand will increase and the above mentioned problems will be ten times more sever making them unmanageable in the upcoming years if no measure is taken. Thus, to face this situation, many strategies have been setup in order to achieve some energy saving in buildings. Among these strategies we find the energy prediction part which deals with hour by hour right energy; the research and elimination part of thermal bridges which its main objective is to reduce as much as possible the energy losses representing around 30% of the energy consumption; and the energy conservation part in wall buildings for future recycling. Our thesis focuses on the last two parts by proposing different methods of CND as well as appropriate survey treatments which allow to highlight structural failure in buildings. Transfer matrix estimation approaches have been used to predict the thermal behavior for a building that is being put under any kind of stress.The main contribution of this thesis concerns the developing of an in-situ storage capacity measuring technique. This is important since there are many softwares proposing the structural composition of a building for a given amount of energy. Nevertheless, there isn’t any method available for confirming or invalidating the results coming from artificial calculations. This thesis brings a solution to this situation by proposing a simple method, with no obstacles, easy to setup and with satisfactory results.
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Modelling and assessment of energy performance with IDA ICE for a 1960's Mid-Sweden multi-family apartment block houseArnaiz Remiro, Lierni January 2017 (has links)
The present thesis has been carried out during the spring of 2017 on behalf of Gavlegårdarna AB. This is a public housing company in Gävle (Sweden) which is a large energy consumer, over 200 million SEK per year, and has the ambitious goal of reduce its energy consumption by 20 % between 2009 and 2020. Many multi-family apartment blocks were built during the "million programme" in the 60’s and 70’s when thermal comfort was the priority and not the energy saving. Nevertheless, this perspective has changed and old buildings from that time have been retrofitted lately, but there are many left still. In fact, one of these buildings will be retrofitted in the near future so a valid model is needed to study the energy saving measures to be taken. The aim of this thesis is to get through a calibration process to obtain a reliable and valid model in the building simulation program IDA ICE 4.7.1. Once this has been achieved it will be possible to carry out the building’s energy performance assessment. IDA ICE has shown some limitations in terms of thermal bridges which has accounted for almost 15 % of total transmission heat losses. For this reason, it is important to make a detailed evaluation of certain joints between elements for which heat losses are abundant. COMSOL Multiphysics® finite element software has been used to calculate these transmittances and then use them as input to IDA ICE to carry out the simulation. Through an evidence-based methodology, although with some sources of uncertainty, such as, occupants’ behaviour and air infiltration, a valid model has been obtained getting almost the same energy use for space heating than actual consumption with an error of 4% (Once the standard value of 4 kWh/m2 for the estimation of energy use in apartments' airing has been added). The following two values have been introduced to IDA ICE: household electricity and the energy required for heating the measured volume of tap water from 5 °C to 55 °C. Assuming a 16 % of heat losses in the domestic hot water circuit, which means that part of the heat coming from hot water heats up the building. This results in a lower energy supply for heating than the demanded value from IDA ICE. Main heat losses have been through transmission and infiltration or openings. Windows account 11.4 % of the building's envelope, thus the losses through the windows has supposed more than 50 % of the total transmission losses. Regarding thermal comfort, the simulation shows an average Predicted Percentage of Dissatisfied (PPD) of 12 % in the worst apartment. However, the actual value could be considerably lower since the act of airing the apartments has not been taken into account in the simulation as well as the strong sun's irradiation in summer which can be avoided by windows shading. So, it could be considered an acceptable level of discomfort. To meet the National Board of Housing Building and Planning, (Boverket) requirements for new or rehabilitated buildings, several measures should be taken to improve the average thermal transmittance and reduce the specific energy use. Among the energy saving measures it might be interesting replace the windows to 3 pane glazing, improve the ventilation system to heat recovery unit, seal the joints and intersections where thermal bridges might be or add more insulation in the building’s envelope.
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Porovnání výpočtu tepelných ztrát dle ČSN 06 0210 a ČSN EN 12831 / Comparison of heat losses calculation by CSN 06 0210 and CSN EN 12831Elcner, Jakub January 2008 (has links)
The diploma thesis deals with comparison of heat loss calculation by CSN 06 0210 and CSN EN 12831. This work contains short introduction to the heat loss calculation, definition of basic terms, detailed analysis of heat loss calculation by both standards, description of exemplar buildings, heat loss calculation and heat requirement for heating of buildings according to particular standards. At the end of the work the comparison and discussion of calculation results is presented.
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Konstrukční detaily z druhotných surovin pro opláštění budov / CONSTRUCTION DETAILS FROM SECONDARY RAW MATERIALS USED FOR BUILDING ENVELOPESmolka, Radim Unknown Date (has links)
One of the important reasons for the choice of the thesis topic are increasing requirements from the persons interested in low-energy, passive or even houses with almost zero energy consumption. During decreasing of the energy demand is within the framework of the idea of sustainable construction not only required to decrease the total energy demand of the buildings, search and solve the critical spots in the building jacketing, but also to use the secondary raw materials as full-value substitutions for commonly used products from the primary raw materials. The thesis tries to contribute to the possible usage of polymeric wastes in building industry. In an early stage of the thesis the main and partial targets together with the consecutive steps leading to their fulfilment were set. Selection of the suitable secondary raw materials, discussion with the specialists, initial sample mixing, finding their thermally – technical characteristics, press mould and fire kiln acquisition was carried out during the stage. The next phase is focused on the application of the products made from the secondary raw materials to the building envelope. The products are moulded according to the thermally – technical properties. Performed moulding approved that the products are fully functional and after reaching the required value of heat conductivity coefficient products eliminate imperfections of the solutions used at present. Strapping product for the threshold door joint is registered at Industrial Property Office of the Czech Republic and at European Patent Office at the same time. Recycled materials put into production represent possibilities how to decrease number of acquired virgin materials, need of primary energy and how to decrease risks connected to the waste disposal. Society is starting positively approaching to the products that are partially or fully produced from the secondary raw materials. Nevertheless, before the products from the recycled materials enter the peop
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Assessing the Thermal Performance of Glazed Curtain Wall Systems : S+G Project Case StudyEmili, Antonella January 2015 (has links)
The improvement of curtain wall thermal performances and the optimisation of the issues connected with this technology can lead to a sensible reduction of the energy consumption of the building as well as to an increase level of occupant comfort and longer durability of the façade. The aim of this work is to improve the curtain wall technology especially as far as the connection between the glass and the frame is concerned, since it is the part that mainly affects the performances of the whole façade. This project focuses on the different aspects of the thermal performance of curtain wall systems in order to achieve a higher thermal performance, meeting the objectives of lowering energy demand, improving durability and enhancing indoor comfort. In order to develop new high performance curtain wall connections and to test their level of performance compared with the state of the art ones, two methods were deployed: a numerical and an experimental one. FEM analysis was performed with the software THERM (LBNL) analysing the profile of surface temperatures and the U-values of the details. In the FEM analysis, different materials and geometries were studied. The experimental characterisation of the thermal energy performance of the studied design options was performed by means of thermometric measurements in a climatic cell. The purpose of the experimental analysis was the verification of the effective improvement of the performance in the new details and the comparison with the simulation, aiming at the validation of the simulation model.
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Vacuum insulation in buildings : Means to prolong service lifeThorsell, Thomas I. January 2006 (has links)
Vacuum insulation panels, VIPs, constitute a new insulation material, 6 to 8 times better than traditional insulation materials, which utilizes the positive influence vacuum has on the thermal properties of certain materials. A VIP is a composite with a flat core enclosed by an envelope preventing the core to fill with gas. The vacuum in the core is vital to reach thermal conductivities down to 0,0035 W/(m K), if the vacuum is lost the panel has reached the end of its service life time. Metal sheets would the preferred material to create an impermeable envelope but would creates a large thermal bridge at the edges of a panel when it folds over the edges of the panel. A serpentine edge has been proposed in order to deal with this large thermal bridge. This serpentine edge has been evaluated first as a numeric model in software and then by measuring on a prototype edge element in a hot and cold plate instrument. Measured temperatures were used to validate the numerical model. Results show that a serpentine edge can greatly reduce the thermal bridge if designed correctly. Another direction taken in the development of the VIP barrier is to use very thin metal layers, metallization layer or coating, incorporated into multi layered polymer composite film. This creates barrier films with very good barrier properties and only small thermal bridges. The modeling of gas flux through films with more than one coating has only just started. Existing models for flux through multi coated films all assume that flux is only taking place through defects in the coating layers, that all defects are of the same size and that all defects are positioned in square lattices. The model discussed herein use the same assumption of flux through pinholes only but it does take defect sizes and positions into account. Barrier film, from a regular vacuum insulation panel, with double coatings has been evaluated in light microscopy to characterize the defects in each of the coatings. The data found have been fed into the model and the results comply well with reported permeabilities of similar barrier films. / QC 20101125
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Undersökning av köldbryggor i balkonginfästningar / Study of thermal bridges concerning balcony connectorsHuynh, Hien, Chung, Nick Sun January 2022 (has links)
Köldbryggor innebär att en del av klimatskalet har en högre värmegenomgång än övriga delar av skalet, vilket är ett problem som ingenjörerna stöter på i varje projekt. Värmeläckage kan minimeras med hjälp av ett isolerande skikt mellan betongplattan och bjälklaget. Idag beräknas inte köldbryggan som orsakas av balkonganslutningen, utan ingår i ett påslag på 30% av den totala transmissionsförlust av byggnaden. Detta leder oss till arbetets syfte som är att undersöka varför det inte är en norm att beräkna köldbryggorna som förekommer vid balkonganslutningar. En empirisk undersökning genomfördes med byggföretagen i Sverige, främst Skåne. Intervjun riktades till konstruktörer, energispecialister, platschefer och arbetsledare, totalt deltagande av intervjuer blev 9 varav ett företag svarade genom enkät. Utifrån intervjuerna framgick det att de två mest använda balkong typerna är den traditionella metoden där balkongen fäst genom betongklackar och balkonger som fäst genom köldbryggebrytande isolering modul. Med hjälp av olika datorprogram kommer ovannämnda balkongtyper användas som referensobjekt där köldbryggor beräknas för att undersöka vilka faktorer och svårigheter som finns vid sådana beräkningar. Balkonger med betongklackar beräknades att ha ett värde mellan 0.4 W/mK till 1.0 W/mK medan balkonger med isoleringsmoduler beräknades till 0.023 W/mK - 0.067 W/mK, detta betyder att den traditionella klack-metoden inte håller värme lika bra som balkonger som är fästa med hjälp av isoleringsmoduler. Under beräkningar visade sig att det finns många faktorer som påverkar köldbryggor med avseende på balkonganslutningen. Exempelvis väggens innehåll, antal fönster, placering av fönster och balkongdörrar, balkongens utformning och i vissa fall är armeringensmängden okänd under planeringsfasen. Alla dessa faktorer varierar från projekt till projekt och gör det väldigt komplicerat att skapa en standardlösning som passar till varje enstaka fall. Utöver dessa faktorer så har det varit bristfälliga anvisningar på hur köldbryggor ska beräknas, detta påvisades genom att många företag som intervjuades utförde sina beräkningar på olika sätt. Slutsatsen är att på grund av alla faktorer och svårigheter samt lågt krav på redovisning av köldbryggor i byggnader, så finns det ingen riktig anledning till att utföra så tidskrävande beräkningar under förutsättning att projektet inte syftar till forskning. Däremot tror vi att detta kommer att förändras med tiden eftersom miljön blir allt viktigare med tiden, troligtvis kommer detta leda till striktare krav gällande redovisning av köldbryggor. / Thermal bridging is the movement of heat across an object that is more conductive than other surrounding materials, which is a common problem that engineers encounter in every project. The heat leakage can be reduced by using insulation between the concrete slab and the joist. Today, the thermal bridging caused by the balcony connectors is not calculated but is included in a 30% lump sum of the total transmission losses of the building. This leads us to the purpose of the work, which is to investigate why it is not a norm to calculate the thermal bridges that occur at balcony connectors. To investigate this, an empirical survey was carried out with construction companies in Sweden, mainly Skåne. The interview was directed to engineers, energy specialists, site managers and supervisors. In total there were nine participants in the interviews and one that responded to the survey. Based on the interviews, it emerged that the two most used balcony types are the traditional method where the balcony is attached through concrete slab and joist and balconies which are attached through an insulated balcony connector. With the help of various software, thermal bridge calculations are performed to investigate factors and difficulties with the balcony connectors. Balconies with concrete slabs were calculated to have a value between 0.4 W/mK to 1.0 W/mK while balconies with insulation modules were calculated to be 0.023 W/mK to 0.067 W/mK, this means that the traditional slab method does not retain heat as well as balconies connectors with insulation modules. The conclusion is that there is little to no reason to calculate such time-demanding calculations due to all the factors and complications. Though we believe that this will change in the future with time as the environment becomes increasingly important over time, this will probably lead to stricter requirements regarding the report of thermal bridges from Boverket.
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