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Análise de sistemas híbridos em estabelecimentos assistenciais de saúde (EAS) visando o conforto térmico e redução de consumo energético / Hybrid systems analysis in healthcare establishments aiming the thermal comfort and energy consumption reductionGrimm, Ana Marta Aragão 08 October 2012 (has links)
No contexto de questões ambientais mundiais, os estabelecimentos assistenciais de saúde (EAS), devido a diversas mudanças apresentadas na fisiologia dos edifícios hospitalares nos últimos 100 anos, se inserem como grandes consumidores de energia. Tais alterações devem-se ao avanço das ciências médicas, a novas tecnologias em sistemas e equipamentos e ao crescimento populacional. O presente trabalho pretende analisar a contribuição do uso de tecnologias passivas em Estabelecimentos Assistenciais de Saúde (EAS) no que tange o desempenho térmico e energético, considerando normas específicas para este uso que exigem áreas assépticas através do uso de tecnologias ativas visando o controle da infecção hospitalar e a qualidade do ar interior. Esta configuração caracteriza para estes edifícios, sistemas híbridos com relação a tecnologias ativas e passivas. O caráter experimental da pesquisa foi realizado através de Simulação Computacional com o Software Energy Plus versão 7.0 em que foi analisado o desempenho térmico e energético de um edifício hospitalar. Inicialmente o edifício foi simulado em condições existentes e posteriormente foram realizadas diversas simulações com diferentes soluções arquitetônicas entre elas a inserção de tetoverde. / In the context of global environmental issues the Healthcare Establishments due to several changes on the physiology of hospital buildings over the past one hundred years have fallen as large energy consumers. Such changes were due to the advancement of medical science, new technologies in systems and equipments, and population growth. The present work intends to analyze the contribution of the use of passive technologies in Healthcare Establishments regarding the thermal and energetic performance considering specific standards for this use that demands aseptic areas through the use of active technologies aiming hospital infection control and indoor air quality. This configuration characterizes for these buildings hybrid systems related to active and passive technologies. The research\'s experimental character was made through Computer Simulation with the Software Energy Plus version 7.0 in which were analyzed the thermal and energetic performance of a hospital building. Initially the building was simulated in existing conditions and afterwards several simulations were made with different architectural solutions, in which was among them the insertion of a green roof.
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Estudo da melhoria do desempenho de sistemas de resfriamento evaporativo por micro aspersão de água / Study of improvement the evaporative cooling system performance by water misting systemsZapaterra, Cássio Luiz Ianni 29 September 2016 (has links)
Disponibilidade dos recursos energéticos junto com o despertar da consciência ambiental criaram um interesse por uma condição climática sensível compatível com os recursos disponíveis. Dentro desse cenário o trabalho se volta à necessidade de se criarem e manterem ambientes industriais termicamente adequados aos processos de produção para minimizar as interferências que as condições ambientais exercem sobre os custos dos processos de produtivos e sobre o consumo energético. Os sistemas de resfriamento evaporativo, por sua vez, têm sido a ferramenta de maior potencial de aplicação na criação de ambientes termicamente adequados aos processos. Este modelo revisto de conforto térmico nos coloca um passo à frente para o aumento eficiência energética na construção de projeto de climatização vinculados a temperaturas interiores que atendam conjuntamente tanto aos ocupantes como às atividades que desenvolvem no interior da área climatizada. Apesar de esse sistema apresentar vantagens operacionais, quando comparado a outros sistemas convencionais, existem certas limitações no seu desempenho. Uma das maiores dificuldades das instalações destes sistemas reside na existência de incertezas em qualquer resultado. Possibilitar um controle dos parâmetros, minimizando os erros de aplicação, evitando criar no ambiente um desconforto de tal grau que inviabilize sua aplicação, é o fundamento deste trabalho. A busca passa a ser pela garantia da aceitabilidade dos resultados do sistema projetado e seus limites de aplicabilidade. O estudo das variáveis que interferem no processo do resfriamento por micro aspersão permitiu desenvolver um processo que alterara esses parâmetros durante o funcionamento do sistema, interferindo, conforme a necessidade no seu desempenho, garantindo a completa evaporação da água micro aspergida. / Energy resources along with an environmental conscience awakening has created an interest in sensitive climate together with a more understanding regarding the use of available resources. Inside this scenario our work focus on the needs of creating and maintaining industrial environments thermally suited to these production processes that seeking to minimize interference that environmental conditions have on the costs of production processes and energy consumption. Evaporative cooling systems, in turn, has been a interesting tool to be used in the creation of thermally suitable environments to these processes. This new revised thermal comfort model puts us a step forward to increase energy efficiency in elaborating air treatment projects linked to indoor temperatures that meet both the occupants and the activities that develop inside the controlled area. Although this system has operational advantages when compared to other conventional systems, there are some limitations in their performance. A major difficulty of the installation envolving these systems is about the existence of uncertainty in any results. To allow the control of these parameters in order to minimize the errors in this kind of application and to avoid creating environmental discomfort to such a degree that prevent the implementation, it is the foundation of this work. The search is to ensure the acceptability of the results of the system designed and their limits of applicability. The study of the variables that affect the cooling process by misting allowed us to develop a process that altered these parameters during operation of the system, interfering, as required in its performance, ensuring complete evaporation of water applied by misting in the area.
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Eventos extremos de temperatura e seus impactos no conforto térmico humano : estudo de caso em Presidente Prudente, Brasil, na perspectiva da geografia do clima /Fante, Karime Pechutti. January 2019 (has links)
Orientador: João Lima Sant'Anna Neto / Resumo: Nos últimos anos as mudanças climáticas têm sido foco de diversas pesquisas de cunho científico e político principalmente após as publicações dos relatórios desenvolvidos pelo IPCC. Segundo o grupo, e fato incontestável para muitos pesquisadores, as mudanças climáticas deverão aumentar consideravelmente o número e intensidade dos eventos meteorológicos extremos. Contudo, tais repercussões não ocorrerão em todos os espaços e com intensidades equivalentes. Cada grupo de acordo com o seu poder aquisitivo, forma organizacional, processo histórico e cultural percebem a eminência do risco de modo singular e, da mesma forma, em um futuro próximo, responderão de modo desigual a partir de mecanismos capazes de se precaverem com maior ou menor resiliência à essas repercussões. Diante desta discussão esta pesquisa teve o objetivo de analisar e pesquisar as repercussões dos eventos extremos, associados a temperatura (frio e calor) e condições de conforto térmico humano e bairros com diferentes padrões socioeconômicos na cidade de Presidente Prudente. A hipótese dessa pesquisa é que a população residente nos setores menos valorizados e mais segregados socio-economicamente é também a camada mais vulnerável e afetada, negativamente, por essas ocorrências extremas e com impactos significativos no conforto térmico e saúde. Para contemplar este universo de análise a pesquisa é composta por três vertentes principais: análise dos eventos extremos de frio e calor e a influência na biometeorologia... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In recent years, climate changes have been the focus of several scientific and political research studies, especially after the publication of reports elaborated by the IPCC. According to the group, as well as an unquestionable fact for many researchers, climate changes should considerably increase the number and intensity of extreme weather events. However, such repercussions will not occur in all spaces and with equivalent intensities. Each group, according to their purchasing power, organizational form, historical and cultural process, perceives the eminence of risk in a unique way and, in the near future, will respond unequally through mechanisms that will be able to be cautious with more or less resilience about these repercussions. Given this discussion, this research aimed to analyze and research the repercussions of extreme events associated with temperature (cold and heat) and conditions of thermic comfort in differents socioeconomic districts in the Presidente Prudente city. The hypothesis of this research is that the population residing in the least valued and most socially and economically segregated sectors is also the most vulnerable and negatively affected by these extreme occurrences layer, with significant impacts on thermal comfort and health. In order to contemplate this universe of analysis, the research consists of three main strands: analysis of extreme cold and heat events and the influence on human biometeorology through thermal comfort and discomfort;... (Complete abstract click electronic access below) / Doutor
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Vers une nouvelle méthodologie de conception des bâtiments, basée sur leurs performances bioclimatiques / Toward a new method of buidling design, based on bioclimatic performancesChesné, Lou 18 October 2012 (has links)
Les règles et usages actuels de conception des bâtiments sont essentiellement basés sur la minimisation des déperditions thermiques, ce qui se traduit par la prédominance de l’isolation thermique comme solution d’enveloppe. Or cette logique n'est pas nécessairement la plus pertinente car des ressources énergétiques existent dans l'environnement, et leur apport mériterait d'être pris en considération. Certaines technologies bioclimatiques, et surtout solaires, existent déjà mais leur utilisation n'est pas du tout généralisée à cause d'un manque de repère sur leurs performances. Pour considérer la démarche bioclimatique, il est nécessaire de pouvoir évaluer à la fois la "qualité énergétique" de l'environnement, et l'aptitude des bâtiments à exploiter cet environnement. La méthodologie présentée dans cette thèse est basée sur le calcul d'indicateurs de performance bioclimatique issus de simulations numériques de bâtiments dans diverses conditions climatiques. La simulation permet de supprimer facilement une ressource pour pouvoir obtenir les besoins d'un bâtiment non impacté par la ressource. Ces besoins peuvent alors être comparés à chaque instant au potentiel de la ressource afin de déterminer un potentiel utile, valorisable par le bâtiment. Il est également possible de comparer les besoins du bâtiment dans la simulation sans et avec la ressource et d'en déduire la quantité d'énergie provenant de la ressource réellement utilisée par le bâtiment pour couvrir ses besoins. Un jeu d'indicateurs est ainsi défini pour toutes les ressources et tous les besoins d'un bâtiment, et adapté plus particulièrement aux besoins de confort thermique (chauffage et rafraîchissement) et à trois ressources de l'environnement (le soleil, la voûte céleste et l'air extérieur). Un cas d'étude est alors choisi pour appliquer cette méthode et les résultats sont analysés à l'échelle du bâtiment tout entier ainsi qu'à l'échelle de chaque paroi. Une première analyse globale, sur toute l'année, permet de fixer des points de repères sur l'état des ressources et l'exploitation qui en est faite par les bâtiments. Dans un second temps, les résultats instantanés sont analysés de manière dynamique, et montrent que ces nouveaux indicateurs permettent de bien caractériser le comportement d'un bâtiment dans son environnement. Enfin, les indicateurs sont utilisés dans une approche de conception des bâtiments, et plusieurs pistes sont explorées. Une étude paramétrique est tout d'abord menée et permet d'observer l'influence du niveau d'isolation sur les indicateurs de potentiel et de performance. Puis ces indicateurs sont utilisés pour évaluer la performance bioclimatique de solutions d'enveloppe solaires. Dans un troisième temps, une optimisation de l'enveloppe est menée selon deux critères : un critère classique de minimisation du besoin, mais également un critère bioclimatique de maximisation de l'exploitation du potentiel solaire. / With the current issues concerning the potential savings in the building sector, reducing building energy consumption is a key point. Up to now, efforts have been focused on insulation to separate the inner ambiance from the fluctuation of the outside air temperature. However, insulating a building from its environment deprives it from the renewable free energy sources which exchange with the envelope, either they are heating or cooling sources. Using the building envelope to exploit these resources is the very principle of the bioclimatic architecture. But bioclimatic systems have never been evaluated regarding the amount of available energy they could use, partly because the energy exchanges between the resources and the building have never been really qualified regarding to the building needs, neither quantified in terms of available energy capacity to meet these needs. The aim of this thesis is thus to propose a method to assess both: - the capacity of the environmental resources to cover the building needs, - the ability of the building to exploit the available energy resources. The method is mainly based on energy simulation and the basic data is a comparison of the behaviour of a building with and without a given environmental resource. The building energy needs without the resource can be compared to the resource potential and this comparison give the useful potential of the resource. Moreover, by comparing the building energy needs in the simulation with and without resource, we can get the amount of energy actually used by the building. From these two quantities, the useful and the exploited potential, a set of indicators can be defined and adapted to thermal comfort (heating and cooling needs) and three resources (sun, sky and air). The indicators are then applied to a study case and the results are analysed not only at the scale of the building, but also at the scale of each part of the envelope. A first analysis of the global results over the year is performed to get a first understanding of the state of the resources and the building performances. In a second step, the values are analysed at each time step, to characterize the behaviour of the building towards the environment. Finally, the indicators can be used to design buildings, in several ways. We performed a parametric analysis of the insulation level over the potential and performance indicators. Then, we used them to assess the bioclimatic performances of existing solar technologies. In a final step, the indicators have been used as criteria to optimize the building envelope parameters. Thus, the envelope parameters are optimized according to the minimization of the energy need, but also according to the maximization of the exploited potential.
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Technical solutions for low-temperature heat emission in buildingsPloskic, Adnan January 2013 (has links)
The European Union is planning to greatly decrease energy consumption during the coming decades. The ultimate goal is to create sustainable communities that are energy neutral. One way of achieving this challenging goal may be to use efficient hydronic (water-based) heating systems supported by heat pumps. The main objective of the research reported in this work was to improve the thermal performance of wall-mounted hydronic space heaters (radiators). By improving the thermal efficiency of the radiators, their operating temperatures can be lowered without decreasing their thermal outputs. This would significantly improve efficiency of the heat pumps, and thereby most probably also reduce the emissions of greenhouse gases. Thus, by improving the efficiency of radiators, energy sustainability of our society would also increase. The objective was also to investigate how much the temperature of the supply water to the radiators could be lowered without decreasing human thermal comfort. Both numerical and analytical modeling was used to map and improve the thermal efficiency of the analyzed radiator system. Analyses have shown that it is possible to cover space heat losses at low outdoor temperatures with the proposed heating-ventilation systems using low-temperature supplies. The proposed systems were able to give the same heat output as conventional radiator systems but at considerably lower supply water temperature. Accordingly, the heat pump efficiency in the proposed systems was in the same proportion higher than in conventional radiator systems. The human thermal comfort could also be maintained at acceptable level at low-temperature supplies with the proposed systems. In order to avoid possible draught discomfort in spaces served by these systems, it was suggested to direct the pre-heated ventilation air towards cold glazed areas. By doing so the draught discomfort could be efficiently neutralized. Results presented in this work clearly highlight the advantage of forced convection and high temperature gradients inside and alongside radiators - especially for low-temperature supplies. Thus by a proper combination of incoming air supply and existing radiators a significant decrease in supply water temperature could be achieved without decreasing the thermal output from the system. This was confirmed in several studies in this work. It was also shown that existing radiator systems could successfully be combined with efficient air heaters. This also allowed a considerable reduction in supply water temperature without lowering the heat output of the systems. Thus, by employing the proposed methods, a significant improvement of thermal efficiency of existing radiator systems could be accomplished. A wider use of such combined systems in our society would reduce the distribution heat losses from district heating networks, improve heat pump efficiency and thereby most probably also lower carbon dioxide emissions. / <p>QC 20131029</p>
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Influence d’un environnement chaud et humide sur les réponses perceptives et physiologiques : applications dans le domaine du sport et de la santé. / Hot and humid environment influences of perceived and physiological responses : sport and health applications.Gonzales, Benoît 03 December 2012 (has links)
La réalisation d’une performance sportive dans un environnement chaud est un challenge majeur que doivent surmonter les athlètes de haut niveau notamment à l’occasion des Jeux Olympiques d’été. Depuis plusieurs décennies, les scientifiques ont tenté de trouver des solutions innovantes. Parmi les réponses proposées, on distingue aujourd’hui le refroidissement corporel préalable ou consécutif à l’effort (le pré et le post-cooling, respectivement), qui permettrait de minimiser les risques d’hyperthermie et améliorerait la récupération de l’athlète. Cependant, les modalités d’utilisation de ces méthodes et leur efficacité font l’objet de conclusions pour le moins contradictoires en raison notamment des techniques de refroidissement mises en œuvre (refroidissement par immersion, vêtements thermorégulants, brumisation…), de la durée d’application, du type d’exercice réalisé et des conditions environnementales explorées. La préparation des Jeux Olympiques à Pékin, en Août 2008, a été une occasion unique de faire un état de l’art sur les méthodes existantes. Nous avons testé chez des cyclistes de haut niveau l’hypothèse selon laquelle une stratégie de refroidissement utilisant une veste garnie d’accumulateurs thermiques permettrait d’améliorer le confort thermique et la performance lors d’un exercice de type anaérobie (Wingate test) et lors d’une épreuve d’endurance de 20 minutes. L’étude menée sur le test de Wingate ne montre aucun effet significatif du pré-cooling sur le pic de puissance ni sur la puissance moyenne mais permet néanmoins d’améliorer significativement (P < 0,05) l’indice de fatigue des athlètes testés. Sur l’épreuve de 20 minutes, le pré-cooling permet une amélioration significative (P < 0,05) de la puissance moyenne développée, du confort thermique et une baisse significative des températures cutanées et rectales. Une autre étude portant sur l’influence de différents maillots sur les réponses physiologiques et perceptives de coureurs cyclistes a montré qu’un maillot constitué de larges mailles offrait un meilleur confort thermique en diminuant significativement (P < 0,05) la température cutanée, mais sans modifier la perception de l’effort. Les bénéfices observés chez les cyclistes de haut niveau nous ont orientés vers la mise en œuvre d’un protocole similaire appliqué à des personnes atteintes de pathologies affectant la thermorégulation. Ainsi, nous avons débuté un protocole de recherche clinique exploratoire visant à étudier les effets du port d’une veste thermorégulante sur les performances motrices et cognitives de patients atteints de sclérose en plaques. Ce protocole, qui a obtenu l’accord du Comité de Protection des Personnes du Grand Est –II, devrait commencer fin 2012. / Abstract: Exercising in the heat and high relative humidity is a major challenge that athletes have to overcome, especially during the summer Olympic Games. For decades, scientists investigated innovative solutions amongst which the body cooling before competing (pre-cooling) or after competing (post-cooling) seemed to be a valuable mean of minimizing hyperthermia threats and increasing the recovery of the athletes. However, contradictory results have been reported concerning body cooling protocols (cold water immersion, cooling vests, water sprays, etc.), exposure time, exercise duration, environmental conditions and their efficiency. By preparing the 2008 Beijing Olympic Games, we managed to review the existing literature on those methods. We hypothesized that a cooling vest combined with a cooling headband would increase thermal comfort of elite cyclists and their performances on an anaerobic (Wingate Test) and endurance (20 minutes time-trial) exercises. The Wingate Test study showed no significant effect of pre-cooling on peak or mean power output despite a significant increase (P < 0.05) of fatigue indexes. During the endurance study, pre-cooling maneuvers induced significant improvement (P < 0.05) of the mean power output, of the thermal comfort and a significant decrease in rectal and skin temperatures. Another study concerning the influence of wearing different cycling shirt on perceived and physiological responses of cyclists showed that a large knitted shirt provided a better thermal comfort by decreasing significantly (P < 0.05) skin temperatures, but without affecting perceived exertion. Those positive results on elite athletes lead us to apply similar cooling strategies on a population experiencing disease-related thermoregulation troubles. We decided to initiate an exploratory clinical study aiming at investigating the effects of a cooling vest on motor and cognitive skills of patients with multiple sclerosis disease. This protocol obtained the clearance of the French National Ethics Committee – East Section II, and should start on the late of 2012.
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Human-urban radiation exchange simulation modelPark, Sookuk 28 April 2011 (has links)
The purpose of this study is to develop an improved human radiation exchange model for use by planners and researchers. Although applicable for all environments, emphasis will be on urban areas.
All processes of radiation exchange between the human body surface and surrounding environments were investigated through human body area factors (effective radiation area factor, feff, and projected area factor, fp), existing human thermal exchange models and three-dimensional (3D) computer simulation models with collected microclimatic data.
For new body area factors, a sample of standing contemporary Canadian adults in normal-weight (male: 31 persons, female: 40) and over-weight (male: 48, female: 20) body mass index (BMI) categories were analyzed. A 3D mean body model was created for each category. Only very small differences in feff and fp were found between genders and BMI categories. Differences in feff and fp values between this study and previous studies were very large, up to 0.101 and 0.173, respectively.
Another common body posture, walking, was also studied for the normal-weight male and female BMI categories. 3D computer walking body models at four stride positions were created. The directionless fp values for walking posture had minor differences between genders and positions in a stride. However, the differences of mean directional fp values between azimuth angles were great enough (up to 0.072) to create important differences in modeled radiation receipt. When both standing and walking postures are considered, the mean feff value of standing (0.826) and walking (0.846), 0.836, could be used. However, fp values should be selected carefully because differences between directional and directionless fp values were large enough that they could influence the estimated level of human thermal sensation.
A new human radiation exchange model was developed using the new body area factors and compared with five existing models and one method (Burt, COMFA, MENEX, OUT_SET* and RayMan models and the six-directional method) using collected microclimatic data observed in Guelph, Ontario, Canada. Most differences between models came from absorbed solar radiation, especially absorbed direct beam solar radiation because of differences in fp* (=fp×feff) and feff or some missing components (feff or view factors). The lowest differences between the new model and the RayMan model alter the net all-wave radiation estimate up to 29 Wm-2, which can be significant in the human thermal exchange model.
For 3D computer estimation, a new human-urban radiation exchange simulation model was developed combining the new human radiation exchange model and improved urban area factors (i.e., albedos and view factors of sunny and shaded building, ground and vegetation surfaces). The results of the new computer model were compared with microclimatic data collected in Nanaimo, B.C., Canada and Changwon, Republic of Korea as well as with two other 3D computer simulation programs, RayMan Pro and ENVI-met 3.1. The differences between the collected data and the new model were very small. Their correlation was very strong, over 0.99 for total radiation. RayMan Pro and ENVI-met 3.1 programs had larger differences, and their correlations with measured data were weaker than the new model’s. Accurate meteorological and urban setting data should be obtained for better results.
The new model will give planners and researchers a simple tool to estimate accurate radiation effects in complex urban areas. / Graduate
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Optimal predictive control of thermal storage in hollow core ventilated slab systemsRen, Mei Juan January 1997 (has links)
The energy crisis together with greater environmental awareness, has increased interest in the construction of low energy buildings. Fabric thermal storage systems provide a promising approach for reducing building energy use and cost, and consequently, the emission of environmental pollutants. Hollow core ventilated slab systems are a form of fabric thermal storage system that, through the coupling of the ventilation air with the mass of the slab, are effective in utilizing the building fabric as a thermal store. However, the benefit of such systems can only be realized through the effective control of the thermal storage. This thesis investigates an optimum control strategy for the hollow core ventilated slab systems, that reduces the energy cost of the system without prejudicing the building occupants thermal comfort. The controller uses the predicted ambient temperature and solar radiation, together with a model of the building, to predict the energy costs of the system and the thermal comfort conditions in the occupied space. The optimum control strategy is identified by exercising the model with a numerical optimization method, such that the energy costs are minimized without violating the building occupant's thermal comfort. The thesis describes the use of an Auto Regressive Moving Average model to predict the ambient conditions for the next 24 hours. A building dynamic lumped parameter thermal network model, is also described, together with its validation. The implementation of a Genetic Algorithm search method for optimizing the control strategy is described, and its performance in finding an optimum solution analysed. The characteristics of the optimum schedule of control setpoints are investigated for each season, from which a simplified time-stage control strategy is derived. The effects of weather prediction errors on the optimum control strategy are investigated and the performance of the optimum controller is analysed and compared to a conventional rule-based control strategy. The on-line implementation of the optimal predictive controller would require the accurate estimation of parameters for modelling the building, which could form part of future work.
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Bridging the divide between resource management and everyday life: smart metering, comfort and cleanlinessStrengers, Yolande Amy-Adeline, Yolande.strengers@rmit.edu.au January 2010 (has links)
Smart metering residential demand management programs, such as consumption feedback, variable pricing regimes and the remote control of appliances, are being used to respond to the resource management problems of peak electricity demand, climate change and water shortages. Like other demand management programs, these strategies fail to account for (and respond to) the reasons why people consume resources in their homes, namely to carry out everyday practices such as bathing, laundering, heating and cooling. In particular, comfort and cleanliness practices together constitute most of Australia's potable water consumption in urban centres, and represent most of household energy consumption. In addition, new household cooling practices involving air-conditioning appliances are the major contributor to the nation's rising peak electricity demand, which overloads the electricity system on hot days, costing consumers millions of dollars each year. The oversight of comf ort and cleanliness practices in smart metering demand management programs is concerning because these practices are continuing to shift and change, often in more resource-consuming directions, potentially negating the resource savings achieved through demand management programs. This thesis aims to bridge the problematic divide between the policies and strategies of demand managers, and the day-to-day practices which constitute everyday life. Using the empirical 'hook' of smart metering demand management programs and the everyday practices of comfort and cleanliness, this thesis develops a practice-based conceptual framework to study, understand and analyse these practices and the ways in which smart metering demand management programs reconfigure or further entrench them. A series of qualitative methods were employed in studying 65 households across four research groups, focusing specifically on the household practices of heating, cooling, bathing, laundering, toilet flushing and house cleaning. In addition, 27 interviews were conducted with smart metering industry stakeholders involved or implicated in delivering demand management strategies. Together, these lines of inquiry are used to analyse householders' existing and changing comfort and cleanliness practices, the role of several smart metering demand management strategies in reconfiguring these practices, and potential avenues and opportunities for further practice change in less resource-intensive directions. In particular, this thesis highlights the inherent contradictions and problems in accounting for everyday practices within the dominant demand management paradigm, and offers an alternative paradigm termed the co-management of everyday practices. The thesis concludes by briefly identifying the ways in which smart metering could potentially constrain or catalyse a transition towards this new paradigm.
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Ventilation par mélange utilisant des dispositifs de diffusion munis d’inserts lobés : analyse des écoulements moteurs et du confort thermique induit / Mixing ventilation using air diffusion devices equipped with lobed inserts : airflow pattern and induced thermal comfort analysisBragança, Pierre 05 October 2017 (has links)
Cette thèse porte sur la ventilation par mélange à haute induction pour le bâtiment au moyen de diffuseurs d’air innovants munis de promoteurs de tourbillons. Il s’agit d’inserts lobés, introduits au sein de diffuseurs d’air commerciaux, sans en modifier le processus de fabrication. L’innovation est née de travaux antérieurs et a fait récemment l’objet d’un brevet européen. Sa mise en situation à l’échelle 1 en conditions typiques de chauffage et de climatisation, constitue l’objectif premier des présents travaux. Par une démarche expérimentale, l’impact des inserts lobés sur la topologie de l’écoulement moteur, sur le confort thermique induit en zone d’occupation d’une cellule climatique thermiquement gardée, et sur les pertes de charges et le bruit générés, sont évalués. Les écoulements moteurs sont analysés par PIV 2D2C grand champ, et le confort thermique est évalué en zone d’occupation à l'aide d’un ensemble de capteurs ponctuels de vitesse et de température et du modèle PMV/PPD de Fanger. Les résultats montrent que les inserts lobés introduits dans le diffuseur, favorisent le mélange du jet qui en est issu avec l’air ambiant à traiter. Le confort thermique en zone d’occupation est amélioré de façon significative, par rapport au cas de référence du même diffuseur sans inserts. L’impact des inserts sur l’acoustique et les pertes de charges n’est pas significatif, ce qui valide l’innovation pour son application immédiate dans le bâtiment. En dernière partie, nous avons comparé la performance des diffuseurs innovants munis d’inserts lobés au diffuseur vortex, présenté sur le marché de la diffusion de l’air comme étant doté d’une grande capacité de mélange, suite à la mise en rotation du jet à l’aide d’ailettes profilées. Les résultats ont montré que l’encastrement au plafond du diffuseur vortex préconisé par le fabricant, dont il résulte l’adhérence immédiate du jet par effet Coanda, inhibe le mouvement de rotation escomptée, et sa performance dans ces conditions est inférieure à celle du diffuseur à inserts lobés. Il résulte de ce constat, la nécessité d’une installation du diffuseur vortex sur conduite apparente pour que sa performance soit réelle ; cela est envisageable pour des locaux commerciaux ou industriels de grande hauteur sous plafond. Les diffuseurs lobés encastrés au plafond, dont on a ainsi démontré la performance, sont parfaitement adaptés aux espaces de bureaux ou d’habitations de faibles hauteurs sous-plafond, et répondent par conséquent au réel besoin de la haute induction dans ce type de locaux. / This thesis deals with high-induction mixing ventilation for buildings using innovative air diffusers equipped with vortex promoters. These are lobed inserts, introduced into commercial air diffusers, without modifying the manufacturing process. The innovation was born from previous work and has recently been the subject of an European patent. The first objective of the present work is to conduct full scale experiments under typical heating and air conditioning conditions. By an experimental approach, the impact of the lobed inserts on the airflow and jet pattern, on the thermal comfort induced in the occupied zone of a thermally guarded climate chamber, and on the pressure drop and the noise generation. Airflow pattern is analyzed by large scale PIV 2D2C, and thermal comfort is evaluated in the occupied zone using a set of temperature and speed sensors and Fanger's PMV / PPD model. The results show that the lobed inserts introduced into the diffusers enhance the mixing between the jet and ambient air whose to be treated. The thermal comfort in the occupied zone is significantly improved, compared to the reference case of the same diffuser without inserts. The impact of the inserts on the acoustics and the pressure drop is not significant, which validates the innovation for its immediate application in buildings. Finally, we compared the performance of innovative diffusers with lobed inserts to the vortex diffuser, presented in the air diffusion market as a high mixing diffuser, because of the rotation generated by profiled fins. The results showed that when the diffuser is flush mounted to the ceiling, which is recommended by the manufacturer, the immediate attachment of the jet due to the Coanda effect inhibits the expected rotational movement. Its performance under these conditions is lower to that of the diffuser with lobed inserts. It follows from this finding that the installation of the vortex diffuser on a free pipe is necessary for its best performance ; this can be performed for high ceiling commercial buildings or industrial buildings. Ceiling flush mounted diffusers with lobed inserts, which we have demonstrated their performance, are perfectly suited for office spaces or homes with low ceiling heights, and therefore meet the real need for high induction in this type of buildings.
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