Although the terms "Human Thermal Comfort" and "Indoor Air Quality (IAQ)" can be highly subjective, they still dictate the indoor climate design (HVAC design) of a building. In order to evaluate human thermal comfort and IAQ, one of three main tools are used, a) direct questioning the subjects about their thermal and air quality sensation (voting, sampling etc.), b) measuring the human thermal comfort by recording the physical parameters such as relative humidity, air and radiation temperature, air velocities and concentration gradients of pollutants or c) by using numerical simulations either including or excluding detailed thermo-physiological models. The application of the first two approaches can only take place in post commissioning and/or testing phases of the building. Use of numerical techniques can however be employed at any stage of the building design. With the rapid development in computational hard- and software technology, the costs involved in numerical studies has reduced compared to detailed tests. Employing numerical modelling to investigate human thermal comfort and IAQ however demand thorough verification and validation studies. Such studies are used to understand the limitations and application of numerical modelling of human thermal comfort and IAQ in indoor climates. This PhD research is an endeavour to verify, validate and apply, numerical simulation for modelling heat transfer and respiration of occupants in indoor climates. Along with the investigations concerning convective and radiation heat transfer between the occupants and their surroundings, the work focuses on detailed respiration modelling of sedentary human occupants. The objectives of the work have been to: verify the convective and radiation numerical models; validate them for buoyancy-driven flows due to human occupants in indoor climates; and apply these validated models for investigating human thermal comfort and IAQ in a real classroom for which field study data was available. On the basis of the detailed verification, validation and application studies, the findings are summarized as a set of guidelines for simulating human thermal comfort and IAQ in indoor climates. This PhD research involves the use of detailed human body geometries and postures. Modelling radiation and investigating the effect of geometrical posture has shown that the effective radiation area varies significantly with posture. The simulation results have shown that by using an effective radiation area factor of 0.725, estimated previously (Fanger, 1972) for a standing person, can lead to an underestimation of effective radiation area by 13% for the postures considered. Numerical modelling of convective heat transfer and respiration processes for sedentary manikins have shown that the SST turbulence model (Menter, 1994) with appropriate resolution of near wall region can simulate the local air velocity, temperature and heat transfer coefficients to a level of detail required for prediction of thermal comfort and IAQ. The present PhD work has shown that in a convection dominated environment, the detailed seated manikins give rise to an asymmetrical thermal plume as compared to the thermal plumes generated by simplified manikins or point sources. Validated simulation results obtained during the present PhD work have shown that simplified manikins can be used without significant limitations while investigating IAQ of complete indoor spaces. The use of simplified manikins however does not seem appropriate when simulating detailed respiration effects in the immediate vicinity of seated humans because of the underestimation in the amount of re-inhaled CO2 and pollutants from the surroundings. Furthermore, the results have shown that due to the simplification in geometrical form of the nostrils, the CO2 concentration is much higher near the face region (direct jet along the nostrils) as compared to a detailed geometry (sideways jet). Simulating the complete respiration cycle has shown that a pause between exhalation and inhalation has a significant effect on the amount of re-inhaled CO2. Previous results have shown the amount of re-inhaled CO2 to range between 10 - 19%. The present study has shown that by considering the pause, this amount of re-inhaled CO2 falls down to values lower than 1%. A comparison between the simplified and detailed geometry has shown that a simplified geometry can cause an underestimation in the amount of re-inhaled CO2 by more than 37% as compared to a detailed geometry. The major contribution to knowledge delivered by this PhD work is the provision of a validated seated computational thermal manikin. This PhD work follows a structured verification and validation approach for conducting CFD simulations to predict human thermal comfort and indoor air quality. The work demonstrates the application of the validated model to a classroom case with multiple occupancy and compares the measured results with the simulation results. The comparison of CFD results with measured data advocates the use of CFD and visualizes the importance of modelling thermal manikins in indoor HVAC design rather than designing the HVAC by considering empty spaces as the occupancy has a strong influence on the indoor air flow. This PhD work enables the indoor climate researchers and building designers to employ simplified thermal manikin to correctly predict the mean flow characteristics in indoor surroundings. The present work clearly demonstrates the limitation of the PIV measurement technique, the importance of using detailed CFD manikin geometry when investigating the phenomena of respiration in detail and the effect of thermal plume around the seated manikin. This computational thermal manikin used in this work is valid for a seated adult female geometry.

The Passivhaus standard is a building methodology that was established in Germany in the 1990s. It uses a passive design strategy to achieve built environment comfort with minimum energy consumption. However, research shows that not every Passivhaus project has been successful in terms of its comfort and energy performance. Passivhaus is a representation of a high-performance, low-energy prototype of sustainable buildings, which, as a new building typology, embraces new ideas of comfort and accommodates a range of occupants who have different attitudes and expectations. Thus, the social grounding of such a new typology needs to be reconsidered. Understanding the phenomenon of Passivhaus living in the UK context forms the starting point of my research. In reflection of existing Passivhaus post-occupancy evaluation (POE) research in the UK, the majority of this research is focused on performance and frequently adopts an approach using prediction and computer simulation. Only a few studies have examined the Passivhaus system from an architectural design point of view. Research into its energy performance lacks a deeper connection with the occupants' perception of comfort and the architectural design of the Passivhaus. This research focuses on the coherence of Passivhaus living and builds up a theoretical framework to understand the Passivhaus system in relation to occupants' daily lives. It argues that by providing more possibilities and opportunities within the design of the built environment for adaptive behaviours and norms of sustainable living, as opposed to stressing energy efficiency and technological advances, the sustainability embodied in the Passivhaus standard can be further actualised. Previous research into the POE field of Passivhaus has employed a predominantly quantitative method. However, the small amount of research conducted using a qualitative approach demonstrates the potential benefits of gaining a better understanding of sustainability in people's perceptions of comfort, their everyday practices and the nature of their energy use. The methodological approach for the proposed research will be qualitative in nature due to the need to understand highly context-bound experiential data. A mixed approach of quantitative and qualitative methods will be explored to collect and analyse data from various aspects related to the subject matter in order to draw valid conclusions. The research uses a combined framework of grounded theory methodology and a multiple case study approach as a way of taking a step back from empirical research and building up an inductive theory-building process. The combination of these two frameworks is tailored for this research, which enables them to complement each other. The research provides an exploration of Passivhaus living and an insight into the delicate relationship between the occupants and their domestic space. The study explores the shifting perception of comfort, the delicate relationship between habitat and inhabitant and the process of adaptation in the Passivhaus to understand the shaping of household behaviour in relation to different contexts and scenarios unique to the Passivhaus industry. The substantive theory that describes this relationship is summarised at the end of the thesis, with the aim of informing potential Passivhaus clients of the system's holistic sustainable design features and to make recommendations for better Passivhaus design to building professionals.

Orientador: Carlos Daniel Ebinuma / Banca: José Luz Silveira / Banca: José Nédilo Carrinho de Castro / Banca: Jeronimo dos Santos Travelho / Banca: Sebastião Cardoso / Resumo: O resfriamento evaporativo consiste na utilização da evaporação da água através da passagem de um fluxo de ar, provocando a redução na temperatura do ar e, apesar de utilizarem tecnologia relativamente simples, ainda são pouco utilizados para o condicionamento de ar em regiões de clima úmido. Este trabalho realiza um estudo dos potenciais e limitações de sistemas de condicionamento de ar por resfriamento evaporativo e evaporativo-adsortivo quando utilizados com o objetivo de propiciar conforto térmico ao homem e reduzir o consumo de energia. Apresenta-se, inicialmente, o princípio de funcionamento de sistemas de resfriamento evaporativo e de desumidificadores por adsorção. A seguir, apresentam-se os resultados dos ensaios de desempenho realizados em um resfriador evaporativo direto e propõe-se um novo sistema a ser utilizado em regiões em que as condições de conforto não podem ser supridas pelo resfriamento evaporativo somente. Estuda-se a aplicação desses sistemas a diversas cidades, caracterizadas por diferentes condições climáticas e conclui-se que os sistemas de resfriamento evaporativo acoplados a um desumidificador adsortivo apresentam perspectivas promissoras, principalmente para aplicação em condicionamento de ar onde existem fontes de calor de baixo custo ou calor residual disponível. A análise das condições do ar de insuflamento demonstra a viabilidade da utilização do sistema proposto para conforto térmico humano em regiões de clima úmido como uma alternativa aos sistemas convencionais de condicionamento de ar, poupando energia e protegendo o meio ambiente. / Abstract: Evaporative cooling consists in using water evaporation through the passage of an air flow, thus decreasing the air temperature. In spite of using simple technology, it is seldon used for air conditioning in humid climate regions. This thesis develops a methodology that can be used to establish potentials and limitations of air conditioning systems by evaporative and desiccant cooling when used for human thermal comfort and lower power consumption. Firstly, the operational principles of evaporative cooling and dehumidification by adsorption systems are presented. Next, the results of performance tests developed on a direct evaporative cooler are described. Finally, a new system to be used in regions where the thermal comfort conditions cannot be supplied only by evaporative cooling is proposed. The applications of this system in several cities, characterized by different climate conditions are studied. It concluded that evaporative cooling systems coupled to a dehumidification adsorption system present promising perspectives, mainly to low cost air conditioning applications where residual heat sources are available. The analysis of the supply air conditions shows the feasibility of the proposed system for human thermal comfort in humid climates as an alternative to conventional air conditioning systems, saving energy and protecting the environment. / Doutor

Made available in DSpace on 2014-06-11T19:30:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-11Bitstream added on 2014-06-13T18:59:52Z : No. of bitstreams: 1 oliveira_la_me_guara.pdf: 2784324 bytes, checksum: 076f01bfc4c089c335c41d4360749ebe (MD5) / Este trabalho analisa edifícios que, devido a sua arquitetura moderna, utilizam grande superfície de vidro nas fachadas apresentando, na maior parte das vezes, problemas de conforto térmico. Como objeto deste estudo decidiu-se por um prédio da UNESP, campus de Guaratinguetá. A análise realizada foi baseada no estudo da insolação (diagrama solar), em medidas locais de temperatura, umidade e no levantamento da carga térmica, objetivando avaliar as condições do edifício e propor soluções visando um melhor conforto térmico com a otimização do consumo de energia elétrica. / This work analyzes buildings that, due to their modern architecture, use a great glass surface in the facades presenting, most of the time, problems of thermal comfort. As object of this study we chose a building of UNESP, campus of Guaratingueta. The accomplished analysis was based on the study of the heatstroke (solar diagram), in measuring temperature places, humidity and in the rising of the thermal load, aiming at evaluating the conditions of the building and to propose solutions seeking a better thermal comfort with the optimization of the consumption of electric energy.

This PhD thesis looks at the issue of heating historic churches. These structures pose particular challenges: they consist of large high volumes, they are composed of materials that are vulnerable to changes in indoor microclimate, they usually possess fabric of low energy efficiency, it is often very difficult to insert new systems without damaging the historic fabric, and they are only very intermittently occupied. Churches are thus particularly difficult to heat satisfactorily; most early churches were entirely unheated. Later, local heating, such as stoves, were introduced to respond to congregations’ demand for comfort. Newer churches then started being built with heating systems from the start. Although these were rarely satisfactory, modern solutions have generally either attempted to provide low-level continuous background heating or concentrated on heating the congregation or a combination of the two. This thesis starts by looking at existing systems for heating churches and the current literature used to establish so-called best practice. It then sets out to investigate whether these solutions are actually working. It starts by establishing the ideal environmental conditions for conservation of the fabric. It uses existing literature on the conservation of museum artefacts, looking at each material found in churches in turn to map the various requirements and see if a set of conditions can be found that will ensure preservation of all the materials involved. Next, the thesis uses monitoring to establish what conditions actually exist in historic churches. Four churches in Cambridge were chosen to conduct an on-site survey. The four case studies adopt different modern heating solutions and each was carefully monitored throughout the year to establish what the exact conditions were. At the same time the thesis recorded thermal comfort and energy performance. There has been no study that brings together information on proper environmental conditions for protection of all the various categories of materials, perceived thermal comfort and energy performance in church buildings so this thesis sets out to provide one. The thesis shows that most modern heating strategies for historic churches fail to satisfy all three strands of environmentally sustainable performance indicators for church buildings, i.e. energy performance, thermal comfort, and the preservation of the historic fabric. It ends by tentatively suggesting how these challenges might be approached. The final section of the thesis details the limitations of the study and the various areas that require further study. Overall the study seeks to provide a useful survey of the existing literature on the subject and raise some important questions about the current strategies being employed for heating historic churches. Although the study is restricted to examples in a relatively small geographical area, the conclusions could be applied generally to other Northern European examples and the implications apply not only to other churches but also similar large-volume historic buildings such as town halls, dining halls and guild halls all over Europe.

One of the biggest challenges of a residential building, when it is designed, is to be energy efficient and to provide simultaneously many hours of thermal comfort throughout the year. So, this was the scope of this thesis: to perform a parametric analysis of thermal comfort and energy efficiency in a house that was designed for the climate of Gotland in Sweden. After that, modifications were introduced to the base model and each scenario was checked for the geographical locations of Thessaloniki, Greece and Barcelona, Spain, in order to decide what option is better. The modifications to the base model were changes in the structure of the external wall (insulation materials and total width), the insulation of the internal wall, the thermal bridges (set to good), the windows (3-pane glazing, schedule opening, external window shading, integrated shading), the installation of HVAC system, photovoltaics with efficiencies 15%, 17% and 22% and the introduction of chimney. Based on the results, the Gotland scenario that included the base model plus the modifications of the external and internal wall, HVAC system, PVs with 22% and external window shading increased the energy use by 18.7% but improved the thermal comfort as the yearly hours of dissatisfaction reduced to 22 from 882, compared to the base model. Similar results were taken from the case with the integrated shading in which the energy increased to 19.3%, but the hours of dissatisfaction declined to 24 throughout the year. Regarding only the energy cost of the house, the best location is Barcelona (without cooling). Nevertheless, when considering the overall thermal comfort, the best place for the house is Gotland, as the building was designed for the cold environment of Sweden and not the hot weather of the other southern cities.

During the first seven to ten days of life chicks are unable to maintain homeothermy, thus providing supplemental heat is critical to their livability and performance. Radiant heaters are the preferred method of providing heat during brooding because they provide a range of thermal comfort options for chicks. Infrared thermography is often used to assess the heat distribution created at the litter surface by radiant heaters. The resulting images provide a good qualitative assessment of heat distribution but do not provide any quantifiable metrics through which to compare the radiant output of heaters. Data acquisition systems were developed to measure the radiant flux emitted by six 11.72 kW radiant heaters and to determine radiant flux ranges preferred by broiler chicks during the first week of brooding. Results showed the radiant output was influenced by heater elevation above the litter and differed between manufacturers. 21 – 41% of the energy available the heaters was emitted to the litter as radiant heat. Chicks exhibited a decreasing preference for radiant flux with age. Maximum preferred radiant flux decreased from 387.0 W·m-2 at day 1 to 248.3 W·m-2 at day 8, while the minimum preferred radiant flux decreased from 61.2 W·m-2 at day 1 to 7.65 W·m-2 at day 8. Net usable area (NUA), or the total floor area within the range of radiant fluxes preferred by chicks, was calculated for each heater. Mean NUA by heater ranged from 45.34 (SE = 3.35 m2) to 21.75 (SE = 1.98 m2). Mean NUA significantly increased with heater mounting elevation (P < 0.0001). Results indicate that radiant heaters from different manufacturers with the same power output do not necessarily produce the same radiant distribution and that the maximum preferred radiant fluxes by chicks may not be realized at manufacturer specified heater mounting elevations.

It is widely recognised that one's ability of adaptation is remarkable and thermal comfort is significantly related to such adaptations. This study proposes an alternative method of predicting adaptive thermal comfort based on the availability of adaptations, in particular behavioural adaptations, which needs quantifications of individual adaptation processes and of interactions between them. The fundamental argument of this method is that exercising an adaptive behaviour leads to an increase in comfort temperature, which is termed adaptive increment in this study. Apart from adaptive increments, this method also determines a baseline thermal comfort temperature (the thermal comfort temperature without adaptations) and a correction factor that considers the factors affecting adaptive behaviours, based on which, the highest operative temperature at which people may still feel thermally comfortable. This may be applied in mixed mode (MM) buildings to achieve a higher air-conditioning (AC) setpoint which may lead to a significant reduction in cooling energy. This method is believed to be flexible in dealing with different environments with various levels of adaptations and likely to be advantageous over the steady-state and adaptive models in predicting thermal comfort temperature of an environment with abundant adaptive opportunities. This study also evaluates ways of promoting the use of adaptive opportunities. It explores how adaptive thermal comfort theories may be used for behaviour modelling and in turn be applied to enhance the energy performances and comfort levels of real buildings. To improve the feasibility of this method key effective adaptive behaviours are studied in detail through lab experiments and field studies. The lab experiment has found the adaptive increment of taking cold water to be 1.5°C which is more significant than the previous literature suggests. When all the studied adaptive behaviours are exercised, the overall adaptive increment is as high as 4.7°C. However, the research has identified some issues associated with the adaptive opportunities studied. These include the existence of constraints on the use of adaptive behaviours, the low availability of some effective adaptive opportunities, the low operation frequency of desk fans and the misuse of windows and AC systems. Despite this, the availability of more adaptive opportunities has been verified to be capable of increasing the highest operative temperature at which people may still feel thermally comfortable: the lab experiment shows that over 80% of the participants can still find it thermally comfortable at an operative temperature of 30°C on the condition that adequate adaptive opportunities are provided; the field study shows that the thermal comfort temperature of occupants increases by at least 1°C when desk fans and cool mats are available. Based on these analyses, it proposes an MM system which encourages occupants to exercise adaptive opportunities and improves both comfort levels and energy efficiency. Building performance simulation results show that the proposed MM system is effective in reducing the reliance on AC systems and promotes effective uses of windows and AC systems. By applying the MM system and the associated passive energy-saving strategies, an office can cut cooling energy by about 90% and the peak cooling load by over 80% during transitional seasons.

This work comprises of a detail study of the impact of building integrated heating (BIH) systems on energy efficiency and thermal comfort. The work has been sponsored by a company called Thermotech AB which supplied the BIH system for twin apartment buildings in Kumla owned by Kumla Bostäder. Comprehensive energy analysis was done using IDA simulation software for the building with normal radiator heating and BIH heating systems. The analysis showed 7.5 % annual savings in favor of the BIH system but since the ground and first floor thermostatic set point was not achieved we are a bit skeptical about the actual savings. Detailed literature study in this regard showed that there was no significant difference in the energy consumption for both of the systems. In the case of thermal comfort there are many citations preferring the integrated heating with features like better comfort, air quality, less noisy system ,flexible room layout and ability to use a sustainable source such as solar power. Simulations for thermal comfort were unable to determine any significant betterment of one system over the other as both were theoretically able to deliver the same comfort. Actual measurements however showed extremely good PPD % values during a hot summer day. Unfortunately a winter measurement could not be taken due to time constraint but is a strong recommendation for further work. A detailed survey was also conducted to gauge the people’s reaction on the system during the past winter. While most of the people were satisfied average PMV of around 0.5, people from lower floors did complain about it being too cold during the winter. Some complained about it being too warm during summer time which is understandable as there no external shades and the ventilation system runs at constant speed. Some people had complains about the air quality and lack of ventilation as well. In conclusion the system’s superior thermal comfort over the conventional radiator circuit cannot be denied but its energy efficiency features may be up for debate. We recommend the system in spite of the additional cost due to the comfort for the occupants and the fact that it utilizes a low temperature source which is much more sustainable and environment friendly then the conventional high temperature sources.

Resumo: O sombreamento promovido por árvores constitui um dos melhores dispositivos externos para controle e redução dos efeitos da radiação solar. Natural e de baixo custo, este recurso é de extrema utilidade para o conforto térmico dos seres vivos, especialmente em países de clima quente, onde a incidência de radiação solar é alta. Este trabalho teve como objetivo avaliar a eficiência térmica do sombreamento natural proporcionado por diferentes espécies arbóreas, por meio de medições de varáveis climáticas e de índices de conforto térmico. A pesquisa foi desenvolvida no município de Botucatu, SP e foram avaliadas as sombras de nove indivíduos arbóreos, sendo três exemplares da espécie pau-terra-da-areia (Qualea dichotoma (Warm.) Stafl.), três da espécie chico-pires (Pithecolobium incuriale (Vell.) Benth.) e três da espécie copaíba (Copaifera langsdorffii Desf.). Foram registrados à sombra e a céu aberto os dados de temperatura do ar e umidade relativa, temperatura de ponto de orvalho e temperatura de globo negro e velocidade do vento, durante o verão, ao longo do dia, com leituras horárias entre 8h e 17h. Adotou-se o delineamento estatístico inteiramente casualizado (DIC). Os resultados foram avaliados por meio dos índices de conforto térmico ITU, ITGU, CTR, e por meio da avaliação para o dia crítico do período analisado. Concluiu-se que houve diferença estatística entre as espécies estudadas e de maneira geral a espécie copaíba foi a que apresentou um maior índice de redução da carga térmica de radiação, sendo a pau-terra-da-areia a que apresentou uma menor redução / Abstract: The shading promoted by trees constitutes one of the best external devices to control and to reduce the effects of solar radiation. Natural and economical, such resource is extremely useful to the thermal comfort of living creatures, especially in counties with hot weather, where the incidence of solar radiation is high. This work aimed at evaluating the thermal efficiency of the natural shading given by different species of trees through measurements of climatic variables and indexes of thermal comfort. The research was developed in Botucatu County (São Paulo) and the shade of nine trees were evaluated; three of the species pau-terra-da-areia (Qualea dichotoma (Warm.) Stafl.), three of the species chico-pires (Phithecolobium incuriale (Vell.) Benth.) and three of the species copaiba (Copaifera langsdorffii Desf.). The air temperature and the relative humidity, the dew point temperature, the globe temperature of Vernon, and the wind speed data were taken in the shade during summer, throughout the day with readings between 8 am and 5 pm in the shade and exposed sun. The completely random statistical design was adopted (DIC). The results were evaluated using thermal comfort indexes THI, BGHI, CTR and using evaluation on the critical day for the period analyzed. It was concluded that there was a statistical difference among the species used and, as a whole, the copaiba species was the one which presented the highest index of radiant thermal load reduction and the pau-terra-da-areia, the one which presented the lowest index / Orientador: Odivaldo José Seraphim / Coorientador: Iran José Oliveira da Silva / Banca: Lucila Chebel Labaki / Banca: Ana Maria Liner Pereira Lima / Mestre