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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.
51

Analysis and simultaion of underfloor heating system for bathrooms in Swedish buildings

Fàbregas, Andreu January 2023 (has links)
The pursuit of reducing energy consumption and enhancing thermal efficiency across various sectors to foster sustainable practices has gained significant prominence in recent years, driven by the global environmental crisis. Sweco consultancy has undertaken a study focusing on underfloor heating systems for bathrooms in low-energy buildings located in Sweden. The objective is to analyse the energy usage and thermal loss to the ground based on the thickness of insulation employed. Literature findings indicate that the thermal loss to the ground should comprise approximately 15 % of the total energy, and there exists a logarithmic relationship between the thermal conductivity and density of the insulation material. In the present study, multiple simulation models were developed using IDA-ICE to assess the supplied energy and the percentage of heating loss through the ground for two typical bathrooms situated on adjacent floors of a residential building in Stockholm. The analysis encompasses scenarios where the construction is directly built on the soil or on a concrete slab, as well as the potential thermal loss from the upper level bathroom to the lower level. The results demonstrate that without an insulation layer the heating loss through the ground is remarkably high, approximately 60 %. When employing an insulation thickness of 200 mm or greater, the distinction between constructing on a concrete slab or on the soil becomes negligible. Furthermore, with a 300 mm insulation thickness, the heating loss percentage decreases to over 15 %. The simulations also reveal that the lower level bathroom can benefit from the energy loss occurring in the upper level bathroom. In instances where there is no insulation, the upper level experiences a 56 % energy loss, resulting in energy savings of over 70 % for the lower level bathroom. By incorporating a 45 mm insulation thickness on the upper level floor, this percentage is reduced to 13 %, leading to energy savings of over 25 % for the lower level bathroom.
52

Optimal uppvärmningsmetod för villor i Stockholmsförort / Best heating system for houses in a Stockholm suburb

Östman, Albin, Eriksson, Rickard January 2014 (has links)
Vid val utav uppvärmningssystem för ett småhus är det viktigt att väga in för ochnackdelar, eftersom alla system är bra på olika sätt. Vilket system kommer är mestlämpligt utifrån husets egenskaper och behov?I detta exmenserbete jämförs fjärrvärme, bergvärmepump och frånluftsvärmepump påett utvalt nyproducerat småhus. Resultatet ska baseras på systemets kostnad, livslängd,underhåll och miljöpåverkan.Resultatet har visat att för detta specifika småhus, har frånluftsvärmepumpen varitdominerande i de utförda kalkylerna. / When choosing a heating system for a house it is important to weigh in the different prosand cons, because every system is good in its own way. Which heating system may be ofinterest, depending on the conditions of the house and its requirements?This thesis will compare district heating, geothermal heating and exhaust air heating on aspecific brand new house. The result will base on the heating systems costs, lifetime,maintenance and environmental impact.The result has proven that for this particular house, the exhaust air heating pump hasbeen dominant in the calculations performed.
53

Jämförelse av klimatavtrycket från tre olika skivmaterial i ett vattenburet golvvärmesystem : EPS, kork och wellpapp

Jacobson, Towa, Skogstad, Mathilde January 2022 (has links)
Byggbranschen står inför en brådskande omställning till en lägre klimatpåverkan från byggnader. Ett sätt att minska påverkan är att implementera byggvaruprodukter och material med lägre klimatavtryck, det vill säga produkter som ger upphov till mindre växthusgasutsläpp under sin livstid. För att kunna göra bättre val behöver branschen en noggrann utvärdering av växthusgasutsläppen från byggprodukter ur ett livscykelperspektiv. Den här studien undersöker vilket av materialen expanderad polystyren (EPS), kork och wellpapp som orsakar minst växthusgasutsläpp under 50 år som skivmaterial i ett golvvärmesystem producerat av företaget Flooré AB. Studien undersöker även skillnaden i klimatpåverkan för skivmaterialen under användningsstadiet, baserat på grundläggningsmetoderna isolerad platta på mark, vanligt för nyare svenska småhus, samt en äldre platta med bristande isolering, vanligt förekommande i hus uppförda i Sverige på 1970-talet. Beräkningen av utsläppen från respektive skivmaterial sker med livscykelanalys som metod och ämnar att bestämma materialens klimatpåverkan (GWP) som utsläppen av koldioxidekvivalenter (CO2e) orsakat av 1 m2 golvskiva i ett golvvärmesystem under ett år. Ettårsperspektivet lägger grunden för en enkel omvandling av skivans klimatpåverkan till valfri tidsram. Den här studien bedömer att golvvärmesystemet bör vara funktionellt i minst 50 år och tittar därför närmare på den livslängden. Studien fastslår att wellpapp i de flesta fall orsakar 14–29 procent lägre växthusgasutsläpp än EPS under ett år som skivmaterial i ett värmegolv beroende på grundläggningsmetod, och ungefär 13–23 procent lägre utsläpp än kork. Som svar på vilket av materialen EPS, kork och wellpapp som orsakar lägst klimatavtryck som 1 m2 skivmaterial i ett golvvärmesystem under 50 år multipliceras materialens utsläpp under användningsstadiet med 50. Resultaten belyser fördelarna med låga värmeförluster i ett golvvärmesystem över tid, då wellpapp orsakar störst växthusgasutsläpp för platta på mark med bristande isolering med 119 kg CO2e/m2 , medan EPS orsakar det lägsta utsläppet på 111 kg CO2e/m2. För fallet med isolerad platta är wellpapp det material som orsakar lägst utsläpp med 7,9 kg CO2e/m2, medan EPS orsakar det högsta utsläppet om 8,9 kg CO2e/m2. Avseende klimatpåverkan är wellpapp det bästa alternativet för implementering som skivmaterial i ett golvvärmesystem med en livslängd på 50 år i nya välisolerade svenska småhus. För äldre småhus som saknar tilläggsisolering är EPS det materialet som orsakar lägst klimatpåverkan, tack vare materialets isoleringsförmåga. / The construction industry is facing an urgent transition to a lower climate impact from buildings. One way to reduce this impact is to implement products and materials with a lower climate footprint, i.e. products that cause less greenhouse gas emissions during their lifetime. In order to make better choices, the industry needs a careful evaluation of greenhouse gas emissions from products used in building production from a life cycle perspective. This study examines which of the materials expanded polystyrene (EPS), cork and corrugated cardboard that causes the least greenhouse gas emissions during a 50-year lifespan as a floorboard in an underfloor heating system produced by the company Flooré AB. The study also examines the difference in climate impact for each floorboard material during the use stage, based on the founding methods thermally insulated slab on ground, common for newer Swedish single-family homes, and an older slab with insufficient insulation, common in houses built in Sweden in the 1970s. The calculation of the emissions from each board is performed with a life cycle analysis method and intends to determine the Global Warming Potential (GWP) of the materials as emissions of carbon dioxide equivalents (CO2e) caused by 1 m2 floorboard in an underfloor heating system for one year. The one-year perspective simplifies conversion of the floorboard climate impact during one year to any other time frame. This study estimates that the system will be functional for at least 50 years, and therefore examines this service time further. The study found that corrugated cardboard, in most cases, causes 14-29 percent lower greenhouse gas emissions than EPS during a year as a floorboard in an underfloor heating system depending on the building's foundation method, and approximately 13-23 percent lower emissions than cork. In response to which of the materials EPS, cork and corrugated cardboard that causes the lowest climate footprint as 1 m2 floorboard in an underfloor heating system for 50 years, the material’s emissions during the use stage are multiplied by 50. The results highlight the benefits of low heat losses in an underfloor heating system over time, as corrugated cardboard causes the greatest climate gas emissions when used with poorly insulated slab with 119 kg CO2e/m2, while EPS causes the lowest emissions of 111 kg CO2e/m2. In a case with insulated slab foundation, corrugated cardboard causes the lowest emissions of 7,9 kg CO2e/m2, while EPS causes the highest emissions of 8,9 kg CO2e/m2. In terms of climate impact, corrugated cardboard is the best alternative for implementation as a floorboard material in an underfloor heating system with a lifespan of 50 years in a newly built and well-insulated Swedish single-family home. For older detached houses that do not have additional slab insulation, EPS is the material that causes the least climate impact, thanks to the material’s insulating ability.
54

Värmeavgivning i ett anisotropt material : Hur påverkas värmeavgivningen från ett värmegolv om wellpapp används som isoleringsmaterial?

Kjellström, David, Sågström, Amanda January 2024 (has links)
Ett experiment har genomförts på en anisotrop golvvärmeskiva i materialet wellpapp utvecklat av Flooré AB. Detta i bland annat syfte av att ta fram värmekonduktiviteten i skivans olika riktningar. Företaget har en golvvärmeskiva i expanderad polystyrenplast (EPS) sedan tidigare. Det är även av intresse att se om parametrar som framledningstemperatur och energiåtgång skiljer sig på ett gynnsamt vis mellan wellpappen och EPSen. Det vill säga om anisotropin kan vara till fördel. Mätningar har genomförts på flertalet provbitar i materialet wellpapp för att bestämma värmekonduktiviteten i wellpappens olika riktningar. Mätningarna analyserades och λ-värden vid 10 ˚C togs fram. Wellpappens värmekonduktivitet i de olika riktningar var högst i den riktning som har högre hållfasthetsvärde och lägre λ-värde gavs i de svagare riktningarna. Därefter användes värdena från analysen i finita elementprogrammet COMSOL. Resultatet från COMSOL matades in i den applikation i Excel som var framtagen av Flooré. Med hjälp av applikationen erhölls optimala framledningstemperaturer på vattnet och effekt per kvadratmeter i vid tre olika värmeeffektbehov där wellpapp och EPS användes som golvskivematerial. Resultatet från applikationen på de olika golvvärmeskivorna jämfördes därefter med varandra. Slutsatserna som drogs var att lägre framledningstemperatur kunde sättas för wellpappskivan eftersom den distribuerade värmen från vattenledningarna bättre än EPSskivan. / An experiment has been carried out on an anisotropic underfloor heating panel in the material corrugated cardboard developed by Flooré AB. The company already has an underfloor heating panel in expanded polystyrene (EPS). It is also of interest to see if parameters such as supply temperature and energy consumption differ in a favourable way between the corrugated board and the EPS. That is, if the anisotropy can be beneficial.  Measurements have been carried out on several test pieces in the material corrugated cardboard to determine the thermal conductivity in the different directions of the board. The measurements were analysed and λ-values at 10 °C were produced. The thermal conductivity of corrugated board in the different directions was highest in the direction with a higher mechanical strength value and a lower λ-value was given in the weaker directions. The values from the analysis were then used in the finite element program COMSOL. The results from COMSOL were entered into the application in Excel that was developed by Flooré. With the help of the application, optimal water supply temperatures and power per square meter were obtained with three different heat flow requirements. This was done for the different materials. The results from the application were then compared with each other. The conclusions that were drawn were that a lower supply temperature could be set for the corrugated board because it distributed the heat from the water pipes better than the EPS board.
55

Infraraudonųjų spindulinių šildytuvų tyrimas / Analysis of infrared heating

Micius, Darius 18 June 2010 (has links)
Tiriamojo darbo tikslas – ištirti spindulinio dujinio šildytuvo darbo režimo parametrus. Dujinis spindulinis šildymas yra ekonomiška, nekenksminga ir labai paprasta šildymo sistema. Tokia šildymo sistema naudojama patalpose su blogu sandarumu, taip pat kur yra dideli aukščiai. Tirtas ,,U‘‘ formos spindulinis dujinis šildytuvas. Tyrinėtos šiluminės savybės spindulinio šildytuvo paviršiaus, kaitimo savybės vamzdžio skirtinguose šildytuvo pjūviuose, vamzdžio įšilimo trukmė, galia šildytuvo, dujų sunaudotas kiekis. Spindulinis dujinis šildymas Lietuvoje mažai ištirtas. / Purpose of work: the research working mode of processed „U“ form radial gas–fired heater. The gas-fired heating is an economical, ecological, harmless and very simply heating system. Such heating system is used in the accommodations with high sealing and there are big height. Were processeded „U“ form radial gas–fired heater. Were explored heating dynamics of radial heater culvert surface, dynamics changing of culvert temperature in characteristic heater operating length section, duration till culvert heats to operating temperature, capacity of processed heater, the gas amount. The radial heating in Lithuanian is few processed and very heavy to do concrete conclusion.
56

Badrumsrenovering i bostäder : Jämförelse mellan radiatorsystem och golvvärmesystem ur energi-, fukt- och komfortaspekt i Västerås

Davidsson, Lukas, Alsterlund, Isak January 2019 (has links)
This degree project cover renovation of sanitary rooms with focus on an exchange from a radiator system to an underfloor heating system out of the three aspects energy, moisture and thermal comfort. The used method is literature study, interview, case study and calculations. When a radiator system is replaced with an underfloor heating system the energy demand will decrease due to a possible temperature reduction. The power requirement for the bathrooms will be reduced if the finish material have a higher density and the volume of the room is small. The moisture aspect can in some cases deteriorate with the replacement of systems. It is possible to achieve the same thermal comfort with any system, but it is easier to adjust with an underfloor heating system. An exchange from a radiator system to an underfloor heating system is possible. The energy and thermal comfort aspects improves, but the moisture aspect will potentially degrade.
57

Aquecimento solar de água e medição individualizada: sistemas para edifícios multifamiliares. / Solar water heating system and individualization: systems for multifamily buildings.

Pimenta, Cristina Cardoso 20 February 2019 (has links)
A matriz energética mundial atual gera inúmeros impactos ambientais e, com isso, fontes de energia alternativas são necessárias para um futuro imediato. Desta forma, a energia solar se apresenta como uma das possíveis alternativas. A energia solar, principalmente quando utilizada para o aquecimento de água, ou seja, na sua forma térmica, não apresenta impactos ambientais durante sua produção e possui um funcionamento simples. Devido aos seus benefícios, sistemas de aquecimento solar de água já são muito utilizados em diversos países e, inclusive, incentivados por leis, como na cidade de São Paulo. Mesmo este sistema já tendo sido muito estudado, quando a sua aplicação é destinada a residências unifamiliares, ainda há algumas lacunas quando se trata da aplicação em residências multifamiliares. Um exemplo de lacuna é a questão da medição individualizada dos sistemas prediais, incluindo da energia solar. Sendo assim, o objetivo da presente pesquisa é encontrar um sistema de aquecimento solar mais apropriado quanto à medição individualizada. Para tanto, são analisados, teoricamente, diferentes sistemas e suas caraterísticas. Além disso, é realizado um estudo de caso para se avaliar as características de um sistema em funcionamento em um edifício localizado na cidade de São Paulo. Utilizando-se da junção dos conhecimentos adquiridos na seção teórica e na seção prática, são simuladas algumas propostas de alternativas do sistema, visando avaliar o comportamento da produção dos mesmos em situações distintas. Ao final é possível identificar que o sistema Solar coletivo com acumulação privado e auxiliar instantâneo privado foi o que atendeu a um maior número dos requisitos gerais de sistemas de aquecimento solar e dos requisitos de individualização, e não apresentou problemas de perdas térmicas significativas, apesar de inovações, vislumbradas para um futuro próximo, terem potencial para elevar ainda mais a qualidade do sistema. / The current global energy matrix generates many environments impacts and, thereby, alternative energy sources are required by an immediate future. Indeed, solar energy is presented as one of the possible alternatives. Solar energy, as more when it heats water, or in other words, when its thermal form is used on the system, does not generate environment impacts during its use and has a simple operation. Due its benefits, solar water heating systems are already widely used in many countries and even encouraged by laws, for example in São Paulo city. Even though this system has already been studied by many scientific researches regarding its application for single family dwellings, there are some gaps when it is related to multifamily dwellings. One example of it is the individualization of the building systems aspect, including the individualization of the solar energy use. Therefore, the aim of this research is find a solar water heating system more appropriated regarding the individualization aspect. Thereunto, different systems from various places are theoretically analyzed by their characteristics. Furthermore, a study case is held to evaluate characteristics of a working system in a residential building located in São Paulo city. Using the junction of both, theoretical and practical studies, some alternative proposals are simulated to evaluate how the production of the systems are in different situations. As a conclusion, it is possible to define the system with a shared solar energy, private boiler and instantaneous auxiliary energy heating as the system that meet a larger number of the general solar heating system requirements and of the individualization requirements and do not have significative thermal loss issues, although, prospected near future innovations have potential to further improve the system.
58

Domestic Heating with Solar Thermal : Studies of Technology in a Social Context and Social Components in Technical Studies

Lundh, Magdalena January 2009 (has links)
Research in solar heating has traditionally focused solely on increasing the system efficiency by improving the technical components. In this thesis the technical methodology and system boundaries are widened to connect the technical aspects with market actors that are highly influential on the implementation of solar technology. The research was focused on how social aspects can be brought into technical studies to improve the understanding of solar heating, and how solar thermal technology can be optimized in a larger energy system. Both heat storage and different system solutions have been investigated. The thesis is built on a number of sub-projects exploring different aspects of solar heating. Improved components and system configurations may result in higher fractional energy savings and thereby make solar energy go from a marginal contribution to be the main energy supplier. Both components and systems are considered in this thesis. The solar heating technology has been shown to work well, also in unique system solutions. Technical possibilities with medium-sized stores for single-family houses and seasonal stores for residential areas are presented. Methods to bring studies of technology and actor studies together are also proposed; domestic hot water use has been modelled based on time-use data, while a multifaceted market situation, in which new system solutions must find their way, has been described by the solar and pellet industries. The complexity of assessing installation and use of a particular heating system in relation to the overall energy system is also discussed. Overall, this thesis shows that successful use of solar heating does not only come down to proper technical solutions, but also depends on the interaction between technology and market actors. A widened perspective, including the social context in which the heating system appears, is then essential. This thesis constitutes a step in that direction.
59

Ein Beitrag zur Optimierung der Betriebsweise heizungs- und raumlufttechnischer Anlagen

Felsmann, Clemens 10 August 2002 (has links) (PDF)
Im Rahmen der vorliegenden Arbeit wird gezeigt, wie ein Gebäude- und Anlagensimulationsprogramm mit bekannten Optimierungsalgorithmen gekoppelt und zur theoretischen Lösung optimaler Steuer- und Regelprobleme in der Gebäudetechnik eingesetzt werden kann. Theoretische Optimallösungen erlauben im Sinne eines optimalen Vergleichsprozesses die Bewertung praktisch anderweitig umsetzbarer Steuerungs- und Regelungsmechanismen. Die im Hinblick auf ein gewähltes Gütekriterium erforderliche Notwendigkeit zur Verbesserung von vorhandenen Steuerungs- und Regelungsszenarien sowie die theoretisch maximal erreichbaren Extremwerte lassen sich leicht abschätzen.
60

[en] INTELLIGENT STRATEGY FOR WATER HEATING BY SOLAR ENERGY / [pt] ESTRATÉGIA INTELIGENTE DE AQUECIMENTO POR ENERGIA SOLAR

PEDRO MARCONDES MONTALEONE 23 November 2018 (has links)
[pt] Esta dissertação analisa aspectos da utilização da energia solar para aquecimento de água. Dois são os aspectos abordados: O primeiro é quanto à utilização de valores médios mensais ou diários de temperatura e insolação utilizados por diversos métodos de dimensionamento ou simulação de sistemas de aquecimento solar, e o segundo é a utilização de múltiplos tanques de armazenamento de água quente ao invés de um único reservatório de maior volume. Assim, este estudo tem como objetivo formular, simular e analisar diferentes cenários de configurações de sistemas de aquecimento solar de água, variando-se o número de reservatórios térmicos para um mesmo volume total do sistema. Tem-se por finalidade atender um mesmo padrão de consumo de água quente, condicionado a um mesmo perfil climático, visando otimizar a contribuição da energia solar ao sistema e consequentemente minimizar o consumo de energia auxiliar elétrica. / [en] This dissertation examines aspects of the use of solar energy for water heating. Two aspects are handled: The first is regarding the use of average monthly or daily values of temperature and insolation used by different scaling methods or simulation of solar water heating systems, and the second is the use of multiple hot water storage tanks instead of a single larger volume reservoir of water. Thus, this study aims to formulate, simulate and analyze different configurations of solar water heating systems scenarios, varying the number of thermal reservoirs for the same total volume of the system. It intends to satisfy the same standard of hot water consumption, under same climatic conditions to optimize the contribution of solar energy to the system and consequently minimize the consumption of electric auxiliary energy.

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