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User-centric approach in the pursuit of improved interior climateKrausz, Roland January 2022 (has links)
The field of building services and the topic of interior user-centric climate has been gaining on importance in recent years. The pandemic of COVID-19 has resulted in an increased amount of time spent indoors, extensive energy usage in the built environment, and has also brought up the important issue of a pleasant interior climate. These two implications have become prominent on top of the ones resulting from the existent, persistently growing threat which is posed on our planet by climate change. Rising temperatures & increasing amount of sunlight, extensive energy consumption due to higher demand for cooling and heating, especially in large buildings (i.e. office buildings) occupied by large amounts of people with different preferences and user habits - these are all challenges we now have to face. Considering these challenges, this thesis suggests how a holistic approach could protect against them, mitigate their further development and so prevent their future impact on us humans. The overarching goal of this thesis, the pursuit of the “ideal” interior climate in office buildings, is achieved through setting up scenarios where different variations of daylighting, thermal comfort and energy consumption will be experimented with. The “ideal” interior climate will then be determined through assessing these scenarios and their corresponding results, yielding a recommendation for building future office spaces - these will no longer be only functional and provide shelter, but will also support interior occupant comfort and be efficient while doing so.
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Simulations of energy efficient windows in a historical building located in mid-SwedenMedrano Eraso, Iñigo January 2023 (has links)
Amorphous silicon photovoltaic windows intend to not only improve thethermal bridge that windows represent but also to collect energy from theradiation incident on the windows themselves. This kind of windows can beapplied anywhere, however to maximize the benefit these can bring it isrecommended for sun-oriented façades. This research aims to investigate theimpacts that this type of windows can have on the energy performance andthermal comfort of a three-story historical stone building in the cold climateof Sweden using the simulation software IDA ICE. The model used for thesimulations had previously been developed and tested in other researches thatinvolved this same building. This research shows that the yearly energyconsumption for the townhall can be reduced down to 280000 kWh,representing a reduction of 5000 kWh compared to the base model, if theHigh transparency windows are applied, representing a reduction of 1,7%.The use of any of the four proposed windows has shown to increase thepercentage of best comfort hours by at least 5% and lowers the percentage ofunacceptable comfort hours at least by a 10%, even having cases with 0 hoursat this comfort level. The upper level of the South façade would be able toprovide the building with 800 kWh yearly, being the level with the highestenergy collection due to having more windows. Approximately every windowcould collect around 90 kWh yearly, which represents 20% of what a solarpanel of the same area correctly oriented could obtain in the same period oftime. Thus, the amorphous silicon photovoltaic windows do not seem to bethe best change despite offering a very promising thermal comfort. Theeconomical viability of this project is what prevents it from being feasiblesince the energy saving/obtaining characteristics are not of great magnitude.
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A hybrid low - temperature heating system in geothermal retrofitting for public buildings in the Mediterranean climateBizimana, Boumediene January 2019 (has links)
More than 50 % of EU’s yearly energy demand is spent on heating and cooling systems with which most of its source is generated from non-renewable fossil fuel [1]. Furthermore, half of the EU buildings are heated with a non-efficient boiler of about 60% or less efficiency [1]. The report released by EU from 1990 to 2007 revealed that fuel combustion and fugitive emission contribute to about 79.3% of total greenhouse gas emissions in CO2 equivalents [1]. The EU-EBPD long-term renovation strategy is to improve the energy performance of all residential and non-residential buildings in its member countries through supporting the renovation of the existing buildings into highly energy efficient and decarbonised buildings [2]. Despite all these EU policies and efforts to replace these non-efficient heating systems, the main challenge is price comparison of different solutions and their efficiency in retrofitting of the heating old systems together with the lack of information about the functioning of those old systems [1]. Thus, the development of an easy to install heating system in retrofitting with low exergy heat supply is a significant contribution to a sustainable solution in minimizing energy resources depletion and environmental emission. Furthermore, efficient system control of these easy to install heating systems, hybrids combinations solution for retrofitting building could be a sustainable solution for the preservation of the existing building. The main objective of this work was to design an easy to install hybrid low-temperature floor heating system in retrofitting buildings and compare its results on energy performance, thermal comfort and indoor air quality with other conventional heating mainly used in the Mediterranean climate. This study was performed in two existing radiators heated buildings located in Sant Cugat del vallès in Catalonia, Spain.The results showed that the hybrid low-temperature heating system has the highest energy performance and energy saving of 48 % and 52% compared to that of existing radiator heating and all air heating, respectively. However, hybrid low-temperature floor heating showed a slow heating response, and consequently, it showed lower operative temperature compared to others even though it was within the recommended standards limits. The hybrid low-temperature heating system with demand-controlled ventilation also showed a better indoor air quality, while as existing radiator with its natural ventilation showed the worst indoor air quality. All three compared heating systems showed a better coefficient of performance with low-temperature heat supply and were able to operate with low-temperature heat supply. / Mer än 50% av EU:s årliga energibehov spenderas på värme- och kylsystem där de flesta av deras källor genereras från icke-förnybart fossilt bränsle [1]. Dessutom värms hälften av EU:s byggnader upp med en ineffektiv panna med cirka 60% eller mindre effektivitet [1]. EU:s rapport från 1990 till 2007 avslöjade att bränsleförbränning och flyktiga utsläpp bidrar till cirka 79% av de totala utsläppen av växthusgaser i koldioxidekvivalenter [1]. EU:s och EBPD:s långsiktiga renoveringsstrategi är att förbättra energiprestanda för alla bostäder och andra byggnader i dess medlemsländer genom att stödja renovering av befintliga byggnader till mycket energieffektiva byggnader [2].Trots alla dessa EU-policyer och ansträngningar för att ersätta dessa ineffektiva värmesystem, är den största utmaningen prisjämförelse av olika lösningar och deras effektivitet i renovering av de gamla värmesystemen tillsammans med bristen på information om hur de gamla systemen fungerar [1]. Därför är utvecklingen av ett installationsenkelt värmesystem med låg värmeförsörjning av exergi ett viktigt bidrag till en hållbar lösning för att minimera energiresurser och miljöutsläpp. Dessutom kan effektiv systemkontroll av dessa värmesystem med olika kombinationslösningar för renovering av byggnaden vara en hållbar lösning för att bevara den befintliga byggnaden.Huvudsyftet med detta arbete var att utforma ett lågtemperaturgolvvärmesystem att använda vid renovering av byggnader och jämföra dess resultat på energiprestanda, termisk komfort och inomhusluftkvalitet med annan konventionell uppvärmning som huvudsakligen används i medelhavsklimat. Denna studie utfördes i två befintliga radiatoruppvärmda byggnadet i Sant Cugat del vallès i Katalonien, Spanien. Resultaten visade att hybridsystemet med låg temperatur har den högsta energiprestandan och energibesparingen på 48% och 52% för den befintliga radiatorvärme respektive luftvärme. Emellertid visade lågtemperaturgolvvärme ett långsamt uppvärmningssvar, och följaktligen visade det lägre driftstemperatur jämfört med de andra systemen trots att det låg inom de rekommenderade standardgränserna. Lågtemperaturvärmesystem med efterfrågningsstyrd ventilation visade också en bättre inomhusluftkvalitet, medan befintliga radiatorer med sin naturliga ventilation visade den sämsta inomhusluftkvaliteten. Alla tre jämförda värmesystemen visade bättre prestanda med lågtemperaturvärmeförsörjning och kunde fungera med lågtemperaturvärmeförsörjning.
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Reversible windows for energy savings : Computer simulations using IDA-ICE softwareLatasa Galíndez, Aitor, Mestre Manrique, Germán January 2023 (has links)
This study looks at how reversible windows can minimize cooling and heating energy use while maintaining thermal comfort in buildings in Sweden and Spain. The growing need for energy-efficient structures and the potential advantages of reversible windows served as the driving forces behind this study. The approach taken in this study is a comparison of energy use of buildings where reversible windows were installed. The windowpanes had properties such that different solar heat transmittance coefficients were attained at the two states of the windows, being altered in spring and autumn. The windows were tested in two different buildings, one in each country, using IDA-ICE software in order to calculate the energy consumption both in winter and cooling, focusing in heating in winter and cooling in summer in order to know if there was a real energy saving compared to the base model used.The major findings indicate that reversible windows significantly reduce cooling and heating energy usage while maintaining thermal comfort levels that are on par with those of traditional windows in buildings. The effectiveness of reversible windows may, however, fluctuate throughout nations, depending on elements including climate, building design, and user behavior. Among themain findings of the study, the ones to be mentioned would be the total energy use reduction in the whole year that add up to 15 % in Sweden and 21 % in Spain and that most of the energy savings came in Summer for both Spain and Sweden. Additionally, the study also made findings regarding the role that awnings play in energy usage, determining that they may be truly significant in terms of reducing electricity bills. The awnings helped reduced the amount of energy used for both climates, in Madrid, the reduction was of 8 % , and in Stockholm it was of 4 % , these findings lead us to believe that the awnings are better suited to warmer climates. This study also investigates the economic viability of this novel kind of windows. The idea was to calculate the extra cost that could be associated to the installation of these newer reversible windows technologies by use of the NPV method to calculate the present value of the future energy savings to know if the money investment of the reversible windows is profitable or not. When comparing the reversible window to the base window both of which share the same U-value an extra 19 % of the base window installation cost could be associated to the new installation of reversible windows (for a 30-year period) for Stockholm, and a 25 % for Madrid. Changing already existing 2-pane windows of ordinary, less insulating quality for the reversible windows, the total energy use is reduced by about 50 % in Spain and in Sweden, but it seems that is just economical for the Swedish model, regarding the well-insulated buildings. An additional conclusion is that, compared to investing in reversible windows on all façades, an investment in reversible windows only on the Southern façade and base windows on the rest becomes a bit more economical, with 25 % allowed extra cost for the reversible windows in Stockholm climate and 27 % in Madrid; however clearly less energy is saved.According to the study’s findings, reversible windows have proven to be useful tools to reduce energy usage in both climates and locations. Meaning that they may play an important role to reduce the impact of the energy crisis that affects the current situation.Reversible windows can lower a building's energy costs and carbon footprint, which can have good economic and environmental effects. For architects, builders, and legislators interested in promoting energy-efficient buildings, the study's findings may be helpful. Reversible windows are highlighted in this research as a viable solution to lower energy use and enhance thermal comfort in buildings, particularly in areas with large temperature and solar radiation changes.
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Parametric study of energy retrofit options for a historical buildingEl Tayara, Khaled January 2022 (has links)
Retrofitting measures in old buildings aimed at reducing energy consumption has become a widespread subject and an urgent matter to counteract the effects of climate change and GHGs emissions. The globe has reaffirmed its agreement taken in COP21 to reduce emissions in COP26. The building sector is one of the culprits with a 70 % future energy consumption forecasted by 2050 i.e., the year certain countries aim to carbon neutral (e.g., Sweden). An old building with a severe problem of energy leakage has been studied under the influence of multiple parameters such as building orientation, shading systems, location, Low-E film and an alternative energy supply (GHP). The original building’s EnU amounted to 194.5 kWh/m2•yr; the parameters were applied and orientation of 90⁰ worked best, if the building was being designed, contrary to this case. However, energy reductions, compared to the base model, were actually achieved with the application of Low-E (5%) films and when substituting the heating demand with a GHP (57.5%), LEF-GHP reached (59.2%) and a corresponding decrease in CO2 emissions. Thermal comfort was best achieved with models that had the highest energy consumption such as LEF and ES making it counterproductive in fulfilling the aim of reducing GHG footprint of Rådhuset. The economic feasibility study showed that the installation of a GHP with at least the COP of 4.0 would lead to a shorter payback period than solely applying LEF. A tailored solution of a change in the energy source such as electrified heat supply from renewables combined with LEFs would reduce the energy and emission impact of any building; this would help the building sector reach the envisioned goal of carbon neutrality in 2050.
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Summer Microclimates and Thermal Perception in Japanese Gardens and Small Urban Parks: Hints for Climate-Adaptive Green Space Designs / 日本庭園及び街区公園における夏季の微気象と感じる暑さ:気候に適応的な緑地デザインに向けての知見Cui, Lihua 25 September 2023 (has links)
京都大学 / 新制・課程博士 / 博士(農学) / 甲第24908号 / 農博第2571号 / 新制||農||1102(附属図書館) / 学位論文||R5||N5471 / DFAM / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 柴田 昌三, 教授 北島 薫, 教授 小杉 賢一朗 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
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Avaliação do conforto térmico de ovinos nascidos em confinamento. / Evaluation of the thermal comfort of sheep born in confinement.RIBEIRO, Neila Lidiany. 24 May 2018 (has links)
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Previous issue date: 2006-02 / Capes / O presente trabalho teve como objetivo determinar os índices de conforto térmico
em instalações para ovinos e analisar os parâmetros fisiológicos e o grau de adaptabilidade
de quatro grupos genéticos de ovinos, em São João do Cariri, PB. Foram utilizados 40
animais, 10 por grupo genético, que foram o Cariri, Morada Nova, Barriga Negra e Cara
Curta, todos fêmeas, alojadas em 4 apriscos. Os dados ambientais analisados foram a
temperatura do ar (TA), umidade relativa do ar (UR), velocidade do vento (Vv),
temperatura de globo negro (Tgn), índice de temperatura do globo negro e umidade
(ITGU), carga térmica de radiação (CTR). Os dados fisiológicos analisados foram: a
frequência respiratória (FR), frequência cardíaca (FC), temperatura retal (TR) e temperatura
superficial (TS), medidos nos horários das 9 e 15 h. O grau de adaptabilidade foi realizado
através do teste de Baccari Júnior. A avaliação dos dados foi realizada por um
delineamento inteiramente casualizado em um fatorial 4x2, sendo 4 grupos genéticos e
dois turnos. Os índices ambientais, no período da tarde, foram superiores aos da manhã e
tiveram seus valores, com exceção da UR e Vv, acima da faixa considerada normal. A TR,
FR, FC e TS no turno da tarde estiveram mais elevados do que no turno da manhã, sendo
que a TR esteve dentro da faixa normal e a FR e FC acima da recomendada. O índice de
tolerância ao calor não apresentou diferença significativa entre os grupos genéticos e
mostrou que os animais, mesmo elevando a FR e FC, apresentaram alta capacidade de
adaptação a região. / The present work had the aim to determine thermal means at installation to ovines
and analyse physiological parameters and way of life degree of 4 genetic groups, in the dry
region of Paraíba. It had been used 40 animais, 10 per genetic group: Cariri, Morada Nova,
Barriga Negra and Cara Curta ,all of them were female ,kept in 4 places by chance .Data
were air temperature (TA), air relative humidity (UR), wind speed (Vv), dark block
temperature (Tgn), humidity and dark block temperature (ITGU), radiation thermal support
(CTR). Physiological data were respiratory frequency ( FR), heart frequency (FC), bottom
temperature (TR) and superficial temperature (TS), evaluated for 9 and 15 h. Way of life
degree was carried out by Baccari Júnior Test. Data evaluation was carried out in
randomized sketching in 4x2, being 4 genetic groups and two periods Environmental
means ,in the afternoon, were upper to the moming ones and had its values, with exception
to UR and Vv, increased to the normal tax. TR, FR, FC and TS in the afternoon were
higher than in the morning, but TR normally and FR and FC upper to the normal. ITC did
not show significance difference among genetic groups and showed that the animais, with
higher FR and FC showed high capacity to the region.
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Adapting a human thermoregulation model for predicting the thermal response of older personsNovieto, Divine Tuinese January 2013 (has links)
A human thermoregulation model has been adapted for predicting the thermal response of Typical Older Persons. The model known as the Older Persons Model predicts the core body temperature and regulatory responses of the older people in environmental exposures of cold, warm and hot. The model was developed by modifying an existing dynamic human thermoregulation model using anthropometric and thermo-physical properties of older people. The Model defines the body as two interrelating systems of the body structure (passive system) and the control system of the central nervous system (active system). The Older person's passive system of the model was developed by meticulously extracting relevant experimental data from selected published research works relating to anthropometric and thermo-physical properties of older people. The resultant body structure (passive system) is a multi-segmented representation of a Typical Older Person. The active system (central nervous system) was developed by the application of a novel optimization method based on the working principles of Genetic Algorithms. The use of Genetic Algorithm enables the complex characteristics of the central nervous system of the older persons to be well represented and evaluated based on available data. Active system control signal coefficients for sweating, shivering, vasodilation and vasoconstriction were explicitly derived based on experimental data sourced from literature. The Older Persons Model has been validated using independent experimental data and its results show good agreement with measured data. Furthermore, the Older Persons Model has been applied to several test cases extracted from published literature and its results show good agreement with published findings on the thermal behaviour of older persons. An interview study conducted as part of this research revealed that, professionals (built environment specialists) found the Older Persons Model useful in assisting to further understand the thermal response of the older persons. In conclusion, the adaptation of an existing human thermoregulation model has resulted in a new model, which allows improved prediction of heat and cold strain of the older person although there exist limitations.
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Design, build and test a passive thermal system for a loft : a roof solar chimney application for South African weather conditionsBeviss-Challinor, Lauren Margaret January 2007 (has links)
Thesis (MEng (Mechanical and Mechatronic Engineering))--Stellenbosch University, 2007. / ENGLISH: The design, construction and testing of a passive thermal system, a roof solar
chimney, for a loft is considered. Unlike conventional solar chimneys the solar
collector is constructed from corrugated iron roof sheets with the aim that it can be
integrated into existing buildings at a lower cost or used in low cost housing
developments. The main objective of the study was to determine the feasibility of
such low-cost design to regulate thermal conditions in a loft, that is heating the loft during winter and enhancing natural ventilation during summer, by carrying out an
experimental and analytical study. The results obtained from the experimental study showed that for winter the solar chimney, having a channel width, depth and length of 0.7 m, 0.1 m and 1.8 m respectively and with a peal solar radiation of 850 W/m², heated the room air 5°C higher than the ambient temperature during the hottest periods of the day, which is only marginally better than a loft with conventional roof insulation. At night, it was found that reverse airflow occurred through the chimney, cooling the loft down to
ambient temperature, due to radiation heat loss from the roof collector to the night
sky. For summer operation, the experimental data showed that the chimney was able
to maintain the loft at ambient temperature and the analytical study found that the
chimney was able to enhance natural ventilation effectively, reaching air exchange rate of 6.6 per hour for the 4.6 m³ volume space. It was also found that the chimney’s performance dropped rapidly and significantly during periods of low solar radiation and at night. A sensitivity analysis illustrated that for both summer and winter operation, the size, tilt angle and absorptivity of the roof collector greatly effected the efficiency and mass flow rates of the system, agreeing well with other literature. These results prove that this low cost solar chimney cooling design was feasible to enhance natural ventilation mainly during hot summer conditions with high solar radiation. Compared to a loft with only conventional roof insulation, the chimney did not perform effectively during the winter to heat the loft up, meaning that winter operation for this specific design is not feasible. Possible improvements to the design include using construction materials with higher thermal capacities to retain heat
energy and ensure continued operation during periods of low solar radiation, as well
as using selective absorber coatings on the collector surface. It is recommended that
further work on the project include the integration of these improvements into the
present design and to use the findings obtained from the sensitivity analysis to
improve system efficiencies. CFD analysis of the test-rig will be insightful as an
additional means to validate and compare with the analytical and experimental data
obtained in this report. With the continuation of these studies, this low-cost solar chimney design can be optimised, validated on a commercial scale and built into existing and new housing developments. Incorporating such a passive thermal device will aid homeowners in air regulation and thermal comfort of their living space as well as saving on energy requirements. / Sponsored by the Centre for Renewable and Sustainable Energy Studies, Stellenbosch University
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NOT ANOTHER SPACE SUIT: Fusing Technology and Indigenous Solutions To Facilitate Thermal ComfortKhairat, Alia 02 May 2013 (has links)
Unseen, unheard and unconsidered, Qatar’s migrant worker population is building one of the richest countries in the world. They labor in Qatar’s high heat index1 climate, which is coincidentally comparable to an Oriental sauna, wearing the most rudimentary of clothes. Working up to 60 hours a week, migrant workers fall victim to heat stress and dozens are hospitalized daily, starting as early as March and increasing in numbers during the peak months of June to August. Since clothes are essentially a “second skin,” affecting the rate and efficiency with which heat is exchanged between the body and its surroundings, a concept garment was designed to improve thermal comfort. Low-tech, indigenous heat-management systems are combined with new technologies and knowledge of human physiology to design a two-layer suit that aims to optimize heat exchange mechanisms. The suit enhances radiation, convection and evaporation by having a snug-fitting inner wicking layer and a loose-cut outer shell, and by using strategically placed vents, perforations, and Phase Change Material (PCM) packs. Using fiction as a medium of social commentary and critical design, the concept suit borrows from the superhero aesthetic to present the migrant worker in a new light. The suit denotes power, symbolizing the superhuman feat these workers perform and their true worth to the economy. Its aesthetic and function aim to improve worker morale and performance. Mapping, scoping and primary and secondary qualitative and quantitative research have been used throughout the design process. This is in addition to an ethnographic study, field observations, material explorations, body storming and experimentation.
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