Submitted by Maicon Juliano Schmidt (maicons) on 2015-05-05T14:17:01Z No. of bitstreams: 1 Leila Maria Tamanini Roman.pdf: 1478472 bytes, checksum: 52db0d09c275b5afd54c35d29758e75d (MD5) / Made available in DSpace on 2015-05-05T14:17:01Z (GMT). No. of bitstreams: 1 Leila Maria Tamanini Roman.pdf: 1478472 bytes, checksum: 52db0d09c275b5afd54c35d29758e75d (MD5) Previous issue date: 2013-01-01 / Nenhuma / Este trabalho apresenta uma avaliação energética, através do software EnergyPlus, de uma sala externa com climatização e um prédio de sete andares com ventilação natural. Para tanto, monitoram-se o consumo de energia mensal, os dados climáticos, características arquitetônicas, número de funcionários, localização e demais características que possam interferir direta ou indiretamente no consumo de energia do ambiente de estudo. Os dados obtidos através de levantamento in loco, memoriais da área de infraestrutura e recursos humanos, juntamente com a análise das faturas de energia elétrica mensais, servem de parâmetro para a simulação, bem como validam os resultados, permitindo a busca de novas alternativas que visem eficiência e redução no consumo. As avaliações são realizadas tendo como base duas edificações pertencentes ao Centro Administrativo de Lojas Colombo, localizadas em Farroupilha, Rio Grande do Sul. A análise visa minimizar o consumo de energia elétrica buscando garantir o máximo de horas em conforto. Para tanto avalia os índices de conforto térmico, as temperaturas internas, os ganhos internos de calor, as condições de operação do ar condicionado na sala externa e a potência necessária de ar condicionado para instalação nas quinze zonas térmicas pertencentes ao prédio, verificando o consumo energético das alternativas utilizadas e a relação custo-benefício. Através das simulações na sala externa constatou-se que, com a utilização de materiais eficientes termicamente, as trocas térmicas do interior com o exterior são minimizadas, o mesmo ocorrendo com a substituição de equipamentos antigos, a exemplo de monitores de tubo. Nas quinze zonas térmicas do prédio, a instalação de um sistema de ar condicionado se apresenta como alternativa para melhorar os índices de conforto térmico em dias com temperaturas mais elevadas ou mais baixas, situações estas em que a ventilação natural não é suficiente para garantir um ambiente confortável. Esta adequação de climatização dos ambientes elevou o consumo com energia elétrica total do prédio em 17%, contudo ocorreu melhora significativa nos índices de conforto térmico. Na sala externa foi obtida uma redução no consumo de energia elétrica de 14% sobre o consumo total e a garantia de 86% de horas ocupadas em conforto. / This study presents the energetic evaluation, through the software EnergyPlus, of an external room with acclimatization and of a seven-story building with natural ventilation. For this, the monthly energy consumed, the climatic data, the architectonic characteristics, the number of people, the location and other characteristics which can interfere directly or indirectly the room’s energy consumption were monitored. The data obtained through in loco survey, memorials of the infrastructure area and human resources, as well as the analysis of the monthly electrical energy bills, are considered as parameters for the simulation and they validate the results, allowing the search for new alternatives that aim at consumption efficiency and reduction. The evaluations are performed based on two buildings which are part of Centro Administrativo de Lojas Colombo, located in Farroupilha, Rio Grande do Sul, Brazil. The analysis aims at minimizing the electric energy consumption with the purpose of ensuring the maximum of comfort hours, so it evaluates the indexes of thermal comfort, the inside temperatures, the inside heat gains, the operation conditions of the air-conditioning in the outside room, and the necessary air-conditioning power for the installation in the fifteen thermal zones which belong to the building, verifying the energetic consumption of the used alternatives and the cost-benefit ratio. Through the simulations in the outside room, it was detected that with the use of thermally efficient material, the thermal exchanges between inside and outside are minimized, the same occurs with the substitution of old equipment, such as tube monitors. In the fifteen thermal zones of the building, the installation of an air-conditioning system is an alternative to improve the thermal comfort indexes in days with higher or lower temperatures. These are situations in which the natural ventilation is not enough to ensure that the environment is comfortable. The air conditioning simulated increased the building energy consumption in 17%, although a significative increase in thermal comfort was achieved. At the external room a 14% reduction in electricity consumption, over the total consumption, and the guarantee of 86% of occupied hours in comfort was obtained.

O ser humano consome grandes quantidades de energia para satisfazer as suas necessidades de conforto. Dentro do setor automotivo, depois da energia consumida com a mobilidade em si, o ar condicionado é o maior consumidor. O sistema de climatização para aplicações automotivas tem características particulares, diferentes de sistemas de climatização para outros ambientes. Em uma aplicação automotiva a variação de condições é bastante significativa, como por exemplo, a carga solar que é imposta, a velocidade do veículo, umidade do ar, as temperaturas interna e externa, variação do número e da posição dos ocupantes no interior do veículo, diferentes regimes de rotação e carga do motor, etc. O sistema deve, portanto, ser projetado para funcionar sob todas estas condições e propiciar condições de conforto térmico com o menor consumo de energia. No presente trabalho o objetivo é o projeto e a simulação de um ciclo de refrigeração que atenda aos requerimentos de carga térmica para um automóvel compacto em um ensaio específico realizado em túnel de vento. A partir da carga térmica, o ciclo de refrigeração é dimensionado seguindo-se o procedimento de projeto, que engloba o dimensionamento dos componentes principais como compressor, condensador, evaporador e o dispositivo de expansão. Os resultados dos cálculos teóricos são comparados com o dimensionamento do veículo real, permitindo se chegar a conclusões sobre o projeto. A avaliação do desempenho do sistema projetado é realizada por meio de um procedimento de simulação proposto, e os resultados comparados com os do veículo testado. O objeto de estudo é o sistema de refrigeração de um veículo compacto de quatro portas de fabricação nacional, submetido a um teste de desempenho do ciclo em um túnel de vento. O procedimento de dimensionamento pode ser usado para o projeto básico do sistema de refrigeração. Os resultados obtidos com o modelo de simulação proposto são bastante razoáveis. O modelo pode ser utilizado para prever o resultado de modificações no ciclo de refrigeração, como a troca de componentes, ou mesmo para prever o funcionamento do sistema sob outras condições de operação. A utilização do modelo fica restrita aos limites da validade dos modelos semi-empíricos dos componentes, não sendo recomendada a utilização fora desses limites. Ainda assim, a faixa de aplicação é grande o suficiente para simular a maioria das condições de trabalho encontradas na climatização veicular. / Human being spends a large amount of energy to satisfy its comfort needs. In the automotive applications, air conditioning is the second larger energy consumption system, after the mobility system itself. The refrigeration system for automotive application has peculiar characteristics, which are different from other refrigeration systems (e.g. buildings, food refrigeration, etc). In an automotive application, variation of several conditions are highly significant, such as the sun load, ambient temperature and humidity, the number and position of the occupants inside the vehicle, different engine loads and speeds and so on. The system must, therefore, be designed to operate satisfactorily under all these conditions and to provide thermal comfort with smallest possible energy consumption. The objective of this work is to present the project and simulation of a refrigeration cycle for a compact size vehicle in order to meet thermal load requirements of a specific wind tunnel test. From the thermal load, the refrigeration cycle is designed according to a design procedure, which includes the sizing of main components such as compressor, condenser, evaporator and expansion device. The results of the calculations are compared with the actual vehicle design. The performance evaluation is achieved by using a proposed simulation procedure, and the simulation results are compared with the actual vehicle test results. The study is conducted on the refrigerating system of a 4-door compact size vehicle locally manufactured, which was submitted to a refrigeration cycle performance test in a wind tunnel. The design procedure can be used for sizing a baseline refrigeration cycle. The results achieved with the proposed simulation model are acceptable. The model can be used to predict the impact of a modification in refrigeration cycle such as a component change, or even to predict the system balance point under different operating conditions. The application of the model is restricted to the range of validation of the component semiempirical models, so that the use beyond these limits is not recommended. The range of application, however, is wide enough to accommodate most of the operating conditions found in the vehicular refrigeration applications.

<p>Nowadays, office buildings often have large temperature variations during the day and building envelope acts as an energy storing mass and damp these effects and so Offices need more cooling because of internal heat sources. But we know that cooling is more expensive than heating and it uses the very good quality of energy sources (exergy). Controlled Active Mass (CAM) is new approach to absorb radiant heating and acts as a passive cooling device. It has direct cooling effect and reduces the peak load. CAM is a new cooling system design with applying the low energy sources and operates at water temperature close to room temperature and increase the efficiency of heat pumps and other systems.</p><p>In this project, we calculated the transient heat transfer analysis for CAM in a very well insulated test room with façade wall, Internal heat generators (such as Manikin, Computer simulator & lighting) and ventilation.</p><p>Then Polished (shiny) CAM constructed from Aluminum sheets with 0.003 m thickness. It is cube shape with 0.6 m length. This size of CAM is according to 2.5 times larger than human body volume and initial water temperature assumed near half of human body temperature. Then in order to more radiation damping (absorption) by CAM, it painted black (also based on color analysis in heat transfer calculation).</p><p>Some velocity and temperature measurement have been carried out on both polished CAM and black CAM, after visualization by smoke and Infrared Camera. And more cases tested to see the effect of façade wall, IHG’s and ventilation inlet temperature. Thermal comfort measurement also have been done for finding PMV, PPD and temperature equivalent for a seated person which is doing an office job with normal closing.</p><p>At the end results discussed which includes the effect of CAM in room, differences between polished CAM and black CAM and effect of main heat sources on both CAM types (Polished / Black).</p>

The paper will highlight the use of heating regimes throughout the twentieth century both in large cathedrals and rural churches of medieval origin in Sweden. How have norms of thermal comfort been balanced against conservation needs of the buildings, their interiors and valuable objects? The choice of heating regime in an old church can be seen as a negotiation between different stakeholders. Together these voices have been articulating a discourse on indoor climate since the late nineteenth century when churches in Sweden were first heated. The historical indoor climate in churches is poorly known but often referred to in discussions on what kind of heating and climate is suitable for interiors and their artifacts. This is why it is important to collect empirically based knowledge on the features of the past climate. The historical indoor climate is shaped by several factors. Here we look at heating regimes, meaning how heating and ventilation systems have been selected, designed and used. By studying decision making regarding the choice of regimes and also what experience was drawn from the application of technology we will better understand the priorities made between comfort and conservation aims and how scientific knowledge has been used (or not used) to reach these aims. / Kulturarvet och komforten: frågan om lämpligt inomhusklimat i kulturhistoriska byggnader under 1900-talet

Energy price are on the way up to a high level that will not diminish in the future make us to focus more on the sustainable development for a better solution of residential houses. Passive house or low energy housing are one of the solution to make residential more environment friendly, in same time it´s a financial security using less energy, and saving money. The last 10 years in Germany and all around Europe the concept of passive house been developed, and people aim to know more about these concept that leading the market more attractive for passive houses. A passive house is a well designed building highly insulated and air tight with mechanical ventilated system for the whole building envelope that minimizes the use of energy for heating [1]. The housing company Mimer has chosen to invest in low energy consumption in every new housing project.  These future plan projects are decided to use less than 75 kwh per square meter annually in purchased energy [2]. This thesis is about new constructed passive houses, and focuses on the evaluations of the temperature, and moisture condition for attic, external walls and joist. Reason for doing this investigation is to see if passive houses fulfill the building codes regarding moisture, and temperature changes, and to find in early stage suspicious changes that could affect badly on the building envelop. The aim of this study is -         Moisture risk analyses of the attic, external walls and joist -         Studying temperature analysis   With highly insulated walls the risk for moistures extra sensitive than normal building construction.  Also during summer time the comfort inside may be surprised by high indoor temperature and one solution for that could be using sun shading.

The aim of this study was to investigate the bio-climatic characteristics of traditional and contemporary residential architecture in three different climatic/geographical regions of Libya, which are represented by Tripoli in the &ldquo / coastal region&rdquo / Gharyan in the &ldquo / mountainous region&rdquo / and Ghadames in the &ldquo / desert region&rdquo / . It was undertaken to understand and evaluate the effects of building layout and orientation, wall thicknesses, ceiling height, construction materials, thermal mass and size of windows, on the resultant thermal comfort conditions of the buildings/dwellings in question. An architectural survey of the dwellings was carried out and indoor and outdoor photos of houses were taken. Temperature and humidity data in pre-determined rooms of the dwellings, in addition to data relevant to exterior weather conditions were recorded by thermo-hygrometers. Residents who had experience of living in both traditional and contemporary dwellings were interviewed informally before preparing a comprehensive questionnaire, which was distributed to them to gather the required data. It was found that traditional dwellings in Tripoli and Ghadames, in their present condition, did not provide the desired level of thermal comfort. This was attributed to a number of reasons. One was the abandonment of these dwellings by their occupants, in favor of those of modern style. The resulting collapse of some parts of adjacent house blocks, which used to provide a degree of protection against climatic conditions when working as a whole block of several attached houses. Another was the introduction of new construction materials that were incompatible with the original ones. However, traditional dwellings in both cities appeared to provide relatively better thermal comfort conditions in comparison with the use contemporary dwellings of recent years, except for those with air conditioning. This situation was different in Gharyan, where the troglodyte dwellings were concerned. These dwellings were thermally more comfortable than the modern ones in the city. This was attributed to the fact that most of the existing troglodyte dwellings still preserved their original features to a large extent. At length, this study recommends that modern types of dwellings should adapt those features of the traditional ones that are more compatible and suitable for the local climatic conditions, in a way which guarantees optimum exploitation of local resources in terms of energy consumption and cost.

Mit Hilfe von experimentellen Untersuchungen wird nachgewiesen, daß sich die nutzerseitig abgegebene Wärmestromdichte des außenwandnahen Fußbodenbereiches nicht allein über die Differenz zwischen der Heizflächen- und Raumtemperatur beschreiben läßt. Die Ableitung verallgemeinerbarer Berechnungsansätze ist Schwerpunkt der Arbeit. Die experimentellen Untersuchungen erfolgen in einem Modellraum in Originalgröße. Meßtechnisch erfaßt werden die Oberflächentemperaturen, die Lufttemperaturverteilung, die Luftgeschwindigkeitsverteilung und die örtliche Gesamtwärmestromdichte der beheizten Fußbodenbereiche. Der konvektive Wärmeübergang wird maßgeblich von der über dem Fußboden umgelenkten Falluftströmung an der Außenwand beeinflußt. Zur Berechnung der örtlichen Maximalgeschwindigkeiten wird ein einfacher Berechnungsansatz entwickelt. Mit Hilfe numerischer Untersuchungen erfolgt ein Vergleich verschiedener Heizsysteme hinsichtlich der Empfindungstemperaturverteilung.

In today’s increasingly energy conscious society, the methods of providing thermal comfort to humans are constantly under scrutiny. Depending on the climate, and the comfort requirements of the occupants, buildings can be designed to heat and cool occupants with passive methods, as well as mechanical methods. In the subtropics, where buildings often need to be heated in the winter and cooled in the summer, a synthesis of these two methods would be ideal. However, there is a disconnect between the integration of passive cooling and mechanical air conditioning, in subtropical architecture. A study of user attitudes, based out of Australia, found that, “Central control of temperatures has been used to cut demand by preventing users from altering thermostats and other parts of the building for microclimate control. In particular, windows are sealed to prevent tampering.”1 Reliance on air conditioning has the everyday person convinced that if we save energy in the right places, we can use air conditioning as much as we like. The same study goes on to state, “Air-conditioning has been assumed to replace the need for climate design features in buildings creating poor thermal design and high energy use.”2 This can be most clearly seen in our public buildings. Fully conditioned buildings pump cool air into sealed envelopes, adjusting the thermostat to regulate thermal comfort year-round, often in a climate in which mechanical air conditioning is needed only four months of the year, and during the warmest hours of the day. Inversely, ventilated buildings provide passive cooling in a climate in which the temperature and humidity are often too high for thermal comfort during the same four months of the year. In his book Natural Ventilation in Buildings, Francis Allard points out that the global energy efficiency movement, begun in the early 1990s, has now emerged as a concept that incorporates active air conditioning and sitespecific climate design of buildings into one holistic approach.3 However, these buildings exist in more dry and temperate climates, and do not fully apply to the subtropics as cooling models. A model is needed for subtropical architecture allowing a building to reach both ends of the spectrum; from natural ventilation, through mechanical ventilation, to mechanical air conditioning. The goal of this thesis is to design a hybrid model for subtropical architecture which maximizes the use of natural and mechanical ventilation, and minimizes the use of mechanical air conditioning. The vehicle for this explanation is the design of an educational facility. Research of thermal comfort needs for occupants in the subtropics was accompanied with observation studies. This research was compared with case study, site and program analysis. The analysis was supplemented by a handbook of passive and mechanical cooling which was compiled to aid in establishing cooling strategies for the design process. The implementation of the research and analysis was brought to a conclusion that successfully achieved the goals of this thesis. By using passive methods to lower the temperature of the air surrounding the classroom buildings, the incoming air used to cool the occupants reached temperatures low enough to be considered comfortable inside the classrooms.

This work presents the use of numerical modeling and simulation for the analysis of transport phenomena in engineering systems including zero boil-off (ZBO) cryogenic storage tanks for liquid hydrogen, refrigerated warehouses, and human-occupied air-conditioned spaces. Seven problems of medium large spaces in these fields are presented. Numerical models were developed and used for the simulation of fluid flow and heat and mass transfer for these problems. Governing equations representing the conservation of mass, momentum, and energy were solved numerically resulting in the solution of velocity, pressure, temperature, and species concentration(s). Numerical solutions were presented as 2-D and 3-D plots that provide more insightful understanding of the relevant transport phenomena. Parametric studies on geometric dimensions and/or boundary conditions were carried out. Four designs of ZBO cryogenic liquid hydrogen storage tank were studied for their thermal performance under heat leak from the surroundings. Steady state analyses show that higher flow rate of forced fluid flow yields lower maximum fluid temperature. 3-D simulation provides the visualization of the complex structures of the 3-D distributions of the fluid velocity and temperature. Transient analysis results in the patterns of fluid velocity and temperature for various stages of a proposed cooling cycle and the prediction of its effective operating term. A typical refrigerated warehouse with a set of ceiling type cooling units were modeled and simulated with both 2-D and 3-D models. It was found that if the cooling units are closer to the stacks of stored packages, lower and more uniform temperature distribution can be achieved. The enhancement of thermal comfort in an air-conditioned residential room by using a ceiling fan was studied and quantified to show that thermal comfort at higher temperature can be improved with the use of ceiling fan. A 3-D model was used for an analysis of thermal comfort and contaminant removal in a hospital operating room. It was found that if the wall supply grilles are closer to the center, the system has better performance in both contaminant removal and thermal comfort. A practical guideline for using CFD modeling in indoor spaces with an effective meshing approach is also proposed.

Nowadays, office buildings often have large temperature variations during the day and building envelope acts as an energy storing mass and damp these effects and so Offices need more cooling because of internal heat sources. But we know that cooling is more expensive than heating and it uses the very good quality of energy sources (exergy). Controlled Active Mass (CAM) is new approach to absorb radiant heating and acts as a passive cooling device. It has direct cooling effect and reduces the peak load. CAM is a new cooling system design with applying the low energy sources and operates at water temperature close to room temperature and increase the efficiency of heat pumps and other systems. In this project, we calculated the transient heat transfer analysis for CAM in a very well insulated test room with façade wall, Internal heat generators (such as Manikin, Computer simulator &amp; lighting) and ventilation. Then Polished (shiny) CAM constructed from Aluminum sheets with 0.003 m thickness. It is cube shape with 0.6 m length. This size of CAM is according to 2.5 times larger than human body volume and initial water temperature assumed near half of human body temperature. Then in order to more radiation damping (absorption) by CAM, it painted black (also based on color analysis in heat transfer calculation). Some velocity and temperature measurement have been carried out on both polished CAM and black CAM, after visualization by smoke and Infrared Camera. And more cases tested to see the effect of façade wall, IHG’s and ventilation inlet temperature. Thermal comfort measurement also have been done for finding PMV, PPD and temperature equivalent for a seated person which is doing an office job with normal closing. At the end results discussed which includes the effect of CAM in room, differences between polished CAM and black CAM and effect of main heat sources on both CAM types (Polished / Black).