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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

The reasonable ways to reduce heat losses from windows

Jia, Gaoxun January 2012 (has links)
The window insulation always plays an important role in building design and thermal comfort, it is one of the main parts needed to be optimized in building envelop. Window insulation is a basic element which can decide the insulation capacity. The large heat loss from the window is the main part of wasting energy, and simultaneously, there is also difficult to explore the new energy source and to improve the current heat generation device efficiency in this energy crisis century. Therefore, building a proper insulated window system is a good approach to keep an acceptable indoor climate as well as to reduce energy use and negative climate effects. On the other hand, there are amounts of old houses and poorly design houses all over the world either in a well developed country or a developing country. Therefore it can form a better atmosphere to optimize the window worldwide. The aim of the thesis is telling the reader what kind of optimization can be done to get better window insulation. This thesis starts with a briefly introduction to give the basic knowledge of heat loss from windows, and then shows the heat loss level in comparison with other parts of building. Afterwards it gives the optimization strategy to make good window glazing and window frames. For frame design, the hollow frame material property and the benefits of insulants filling window system are described. There are still some problems which exist for the energy efficient windows, such as condensation problem. The thesis also shows this kind of problem and the solution approach.
2

ENERGY AUDIT of GEFLE VAPEN

Sui, Chen January 2009 (has links)
<p>The energy audit is a very interesting and complex work. The building energy audit is defined as a process to evaluate where the energy used in the building structure and to identify the opportunities of reduce energy consumptions. In this paper, it is a first time detailed study of energy audit for me. In this research, the object is to find is it necessary to improve the ventilation systems. So the first step is to estimate how much energy consumed in the building and to find out the saving potential.The major mission in this thesis is that to make a basic energy audit which is include the heat losses from the building and the heat supply in the building. The major heat losses are transmission losses, ventilation losses, heat losses from hot tap water and infiltration losses. In this project the first three types of heat losses could be find out by some useful methods but the infiltration losses is hard to measure. On the other side, the heat supply are composed by district heating , free heating from people inside, free heating from electricity applications and sun irradiation.To make an accurate and complete energy audit is essential for finding out where the energy consumption could be reduced. And this is what I am going to do in this thesis work.</p>
3

ENERGY AUDIT of GEFLE VAPEN

Sui, Chen January 2009 (has links)
The energy audit is a very interesting and complex work. The building energy audit is defined as a process to evaluate where the energy used in the building structure and to identify the opportunities of reduce energy consumptions. In this paper, it is a first time detailed study of energy audit for me. In this research, the object is to find is it necessary to improve the ventilation systems. So the first step is to estimate how much energy consumed in the building and to find out the saving potential.The major mission in this thesis is that to make a basic energy audit which is include the heat losses from the building and the heat supply in the building. The major heat losses are transmission losses, ventilation losses, heat losses from hot tap water and infiltration losses. In this project the first three types of heat losses could be find out by some useful methods but the infiltration losses is hard to measure. On the other side, the heat supply are composed by district heating , free heating from people inside, free heating from electricity applications and sun irradiation.To make an accurate and complete energy audit is essential for finding out where the energy consumption could be reduced. And this is what I am going to do in this thesis work.
4

Evaluation of heat losses from a domestic hot water circulation system

Salazar Navalón, Pablo January 2015 (has links)
Heat losses are an important problem in domestic hot water circulation systems. Therefore, to reduce these losses becomes an issue of utmost importance both economically and environmentally. Nevertheless, it has not been until recent years when these losses have been studied further. Commonly studies have focused on the heat space system operation or radiator system. This study focuses on heat losses in the domestic hot water circulation through the piping system in a building at a school located in Gävle (Sweden) using non-destructive flow and temperature reading devices. The heat used by the school is provided by the district heating network that feeds several heat exchangers. The heat losses, at the same time, will be compared with simulation and theoretical procedures to corroborate them. The domestic hot water piping system of this study consists on more than 1200 meters of insulated copper pipes with different diameters and different insulation thickness. The system was measured for one week (April 26, 2015 to May 3, 2015) when there are working days and nonworking days. A 5% of the annual district heating consumption in the school was calculated as heat losses in the domestic hot water circulation system in the building studied. Finally, improvements in insulation system and changes in the domestic hot water temperature have been simulated and they demonstrate that savings of up to 35% of the heat losses can be achieved and produce significant energy savings.
5

EVALUATION OF HEAT LOSSES FROM ADOMESTIC HOT WATER CIRCULATIONSYSTEM

Salazar Navalón, Pablo January 1900 (has links)
Heat losses are an important problem in domestic hot water circulation systems. Therefore, toreduce these losses becomes an issue of utmost importance both economically andenvironmentally. Nevertheless, it has not been until recent years when these losses have beenstudied further. Commonly studies have focused on the heat space system operation or radiatorsystem. This study focuses on heat losses in the domestic hot water circulation through thepiping system in a building at a school located in Gävle (Sweden) using non-destructive flowand temperature reading devices. The heat used by the school is provided by the district heatingnetwork that feeds several heat exchangers. The heat losses, at the same time, will be comparedwith simulation and theoretical procedures to corroborate them. The domestic hot water pipingsystem of this study consists on more than 1200 meters of insulated copper pipes with differentdiameters and different insulation thickness. The system was measured for one week (April 26,2015 to May 3, 2015) when there are working days and nonworking days. A 5% of the annualdistrict heating consumption in the school was calculated as heat losses in the domestic hotwater circulation system in the building studied. Finally, improvements in insulation system andchanges in the domestic hot water temperature have been simulated and they demonstrate thatsavings of up to 35% of the heat losses can be achieved and produce significant energy savings.
6

Mikroklimato tyrimai įvairiai apšiltintose karvidėse / Microclimate research in the warm various cowsheds

Miškinis, Marius 09 June 2009 (has links)
Santrauka Darbo apimtis 52 puslapiai, įskaitant 39 paveikslėlius ir 4 lenteles. Informacijos šaltinių sąraše 35 šaltiniai. Darbo pradžia 2007 09 01, pabaiga 2009 05 28. Tyrimų objektas. Trijų tipų karvidžių mikroklimatas: apšiltintu stogu 400 vietų boksinė karvidė; šalta 240 vietų boksinė karvidė, bei 130 vietų su perdengimu pusiau gili karvidė. Tyrimų tikslas – įvertinti įvairiai apšiltintų karvidžių mikroklimatą šiltuoju ir šaltuoju metų laikotarpiu, bei nustatyti šilumos nuostolius tvartuose. Išnagrinėjus literatūroje paskelbtus tyrimų duomenis galima daryti išvadą, norint, kad gyvulių produktyvumas būtų didžiausias, o pašarų sąnaudos – mažiausios, karvidėje optimali rekomenduotina temperatūra turi būti nuo -7 iki +24 oC. Tačiau mokslininkų nustatyta, kad jei gyvulius gerai šersime ir jie bus produktyvūs, tai minus 15 oC ir dar žemesnė temperatūra nėra pavojinga. Šiltuoju metų laikotarpiu tyrimais nustatyta, kad karvidžių mikroklimato parametrai buvo optimalūs ir neviršijo rekomenduojamų normų, o šaltuoju metų laikotarpiu santykinis oro drėgnis 15,3 % viršijo optimalius mikroklimato reikalavimus, o ypač didelis buvo iki 95 % apšiltintoje pusiau gilioje karvidėje. To priežastis, kad norint palaikyti tvarte aukštesnę temperatūrą buvo per daug pridaryti vėdinimo kanalai. Apskaičiavus šilumos nuostolius karvidėse nustatėme, kad didžiausi šilumos nuostoliai būna su pašalinamu iš patalpos oru (81 % nuo bendrų nuostolių). / Summary Scope of work pageis 52, including 39 pictures and 4 tables. The information sources listed 35 sources. Beginning in 2007 09 01, the end of 2009 05 28. Work item. Three types of cowsheds microclimate: warm roof of 400 seats box cowshed; cold of 240 seats box cowshed, and 130 seats with a semi-deep reroof cowshed. The aim - evaluate the warm various cowsheds microclimate warm and cold seasons, and to determine the heat losses from stables. The examination of the literature published research data it can be concluded for that animal productivity is highest, while feed costs - the minimum, recommended cowshed optimum temperature must be between -7 to +24 oC. However, researchers found that if the stock is well feeder, and they will be productive, it is minus 15 ° C and lower temperatures are not dangerous. In warm season during the research found that cowsheds microclimatic parameters were optimized and did not exceed the recommended rate, and cold season period, the relative humidity is 15,3% above the optimum microclimatic requirement, in particularly was high up to 95% in the warm semi-deep cowshed. The reason that, in order to maintain a higher temperature in the stables during impose a lot of ventilation ducts. Calculated heat loss cowsheds found that the maximum heat loss is to be with removable from the room air (81 % of the total losses).
7

Vytápění a větrání výrobní a skladové haly / Ventilation and heating system of a production and storage hall

Bližňák, Jakub January 2009 (has links)
The objective of this master thesis is to design heating and ventilation systems for a production and storage hall and a contiguous administrative part of the building. The basis of design is in calculation of thermal losses and gains of the building. The objective of design is to reach requisite microclimate for single spaces and operations. System of heating, ventilation and cooling are elaborated in drawing documentation.
8

Energy analysis between traditional hot water circulation system and an innovative pipe-in-pipe system

Abellán Guallarte, Alejandro January 2022 (has links)
We are at a time when energy efficiency and the reduction in the use of non-renewable energy is an important objective in all aspects and will continue to be so, therefore it is necessary to try to reduce energy and heat losses in the systems used in homes and, in particular, in the domestic hot water (DHW) system. This study aims to find out the advantages and disadvantages of an innovative pipe-in-pipe (PIP) system for DHW circulation with respect to the conventional system of two separate pipes. Previous studies have shown that DHW circulation is indeed an important point of energy losses in the home and that it is possible to reduce these losses by using the innovative system under study. The properties and coefficients defining the heat transfer system have been obtained for both the traditional and innovative systems by using empirical equations and iterative processes, indicating a 32% reduction in heat losses in favour of the pipe-in-pipe system. However, this result has been obtained in a kind of case study, using some simplifying assumptions, needed to accomplish to work within limited time. So the result could vary if a somewhat different system is studied, which is why it is necessary to carry out further studies and research on this subject in order optimize DHW systems in buildings.
9

Daugiabučių namų šiltinimo sprendimų lyginamoji analizė / Multi-home insulation comparison analysis of decisions

Jurkonytė-Pantelejevienė, Morta 14 June 2011 (has links)
Pastatu apšiltinimas, renovacija nagrin(jama jau daug metu, tai aktuali tema daugelyje šaliu. Renovuotuose pastatuose maž(ja šilumos suvartojimas, did(ja busto kaina. Darbo tikslas – nustatyti šilumos taupymo daugiabuciame pastate galimybes gerinant atitvaru charakteristikas, galimybiu analizei taikant ArchiCad EcoDesigner programini paketa, nustatyti programos galimybes, parenkant renovuojamu pastatu atitvaru charakteristikas. Pastatams pritaikomi trys energijos taupymo paketai: standartinis, vidutinis ir maksimalus, paketai lyginami tarpusavyje. Darba sudaro 6 dalys: ivadas, trys skyriai, išvados ir literaturos sarašas. Darbo apimtis - 69 puslapiu be priedu, 68 paveikslas, 11 lenteliu, 35 literaturos šaltiniai. / House heating and renovation has been the topic of research for many years and is an important issue in many countries today. House renovation brings savings over a certain period of time and it is very important that the resident would feel the benefits. The purpose of this work is to identify heat saving posibilities in multi-storey houses by bettering the characteristics of external house walls, comparing them to the ones of houses under renovation and by using the ArchiCad EcoDesigner software package for the possibility analysis establishing the capabilities of the software package. The houses are introduced with three energy saving packages: standard, medium and maximal, the packages are compared with each other as well. The work consists of 6 parts: Introduction, Three chapters, conclussion and the bibliography. The volume of the work- 69 pages without apendixes, 60 picture, 9 tables, 35 bibliography.
10

Värmeförluster vid utvändigt placerade ventilationssystem / Thermal heat losses on exterior ventilation systems

Ahlgren, Tobias, Eliassi, Jalal January 2012 (has links)
To be able to handle tomorrows need for limited energy consumption we need to reduce our use of energy. The building sector stands for around 40 % of all energy consumption in the society. The government has put up a goal to reduce the energy consumption in our buildings with 20 % by year 2020 and 50 % by year 2050 compared with year 1995. To be able to do reach that goal we need a more energy efficient building stock. The main part of the energy used in our buildings is used for space heating. By installing ventilation systems with heat recovery on the exhaust air it is possible to use the heat-energy in the exhaust air to warm up the incoming air. This can contribute to a reduction in energy use. A ventilation system with heat recovery on the exhaust air is space demanding and there can be problems with finding enough space to do the installation indoors. Therefore it can be an advantage to place the aggregate and the ducts on the outside of the buildings climate shell. A placement exterior of the buildings climate shell or in an unheated space leads to thermal heat losses. The aim with this essay is to investigate how significant the heat losses are on exterior placed ventilation systems. The investigation has been done with help of theoretical calculations and measurements of the temperature difference in the ventilation ducts. Analysis has been made on life cycle costs on how to reduce the heat losses in an economic manner. To buildings, Höstvägen 14 and 22 in Växjö, which have been equipped with exterior placed ventilation systems have been studied. The two buildings have two different types of installation of the ducts. Our result shows that the heat losses through the ventilation systems on Höstvägen 14 and 22 are significant. The majority of the losses occur in the ducts. In the aggregate the thermal bridges in the framework accounts for the larger part.

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