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Este trabalho apresenta a analise do efeito da concentração da mistura etilenoglicol / água, pressão do sistema, rotação da bomba e temperatura, sobre o fenômeno cavitação em sistemas de arrefecimento, tendo dois principais objetivos: 1 Explorar as principais características do fenômeno cavitação, através da analise crítica e citação de publicações existentes; 2 Mapear as condições de trabalho de um sistema de arrefecimento, para então simular em bancada as interações da variação dos fatores citados acima, comparando os resultados com publicações já existentes, contribuindo então com um banco de dados que possibilite a otimização do dimensionamento de novos sistemas de arrefecimento. / This work presents the effect analysis of the water / ethyleneglycol mixture, system pressure, pump speed and temperature upon the cavitation phenomenon in cooling systems. Moreover, it has two main targets which are: 1 To explore the main features of the cavitation phenomenon through a critical analysis and citation of available publications; 2 To monitor the cooling system work conditions in order to simulate in a test rig the variation of the parameters described above, understanding its interaction, for than to provide a database that make possible the design optimization of new cooling systems.

Este trabalho apresenta a analise do efeito da concentração da mistura etilenoglicol / água, pressão do sistema, rotação da bomba e temperatura, sobre o fenômeno cavitação em sistemas de arrefecimento, tendo dois principais objetivos: 1 Explorar as principais características do fenômeno cavitação, através da analise crítica e citação de publicações existentes; 2 Mapear as condições de trabalho de um sistema de arrefecimento, para então simular em bancada as interações da variação dos fatores citados acima, comparando os resultados com publicações já existentes, contribuindo então com um banco de dados que possibilite a otimização do dimensionamento de novos sistemas de arrefecimento. / This work presents the effect analysis of the water / ethyleneglycol mixture, system pressure, pump speed and temperature upon the cavitation phenomenon in cooling systems. Moreover, it has two main targets which are: 1 To explore the main features of the cavitation phenomenon through a critical analysis and citation of available publications; 2 To monitor the cooling system work conditions in order to simulate in a test rig the variation of the parameters described above, understanding its interaction, for than to provide a database that make possible the design optimization of new cooling systems.

Abstract There is much rich solar energy in Taiwan situated at the subtropics;Therefore it¡¦s suitable for solar energy is utilized as the driving energy for absorption cooling system. Simultaneously the use of solar energyreduces our dependence on fossil fuel ,and reaches the goal of energy conservation and reduction of carbon footprint deeply.After establishing absorption cooling system in TRNSYS.16 platform, climate data TMY2 form for several cities of Taiwan are input to the simulation program. As a result of Taiwan climate variation, summer is getting more and more longer ; winter is getting shorter gradually .Hence we simulated program from March to October .Then system operating the parameters of solar collector area and the volume of the storage tank are varied to research those effects on the system performance. The research focuses on the simulation data for monthly solar fraction(f),seasonal solar fraction(F) as well as how much solar energy saved could transform carbon dioxide content for single effect and double effect absorption cooling system operated under the climate of the major cities in Taiwan .Those data could provide the design needs.

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Diploma work is bent on technology production cold with usage absorbing circulations powered heat energy. Work it is possible divide by to the of several part. First volume of work is introduction tenet absorbing circulations, their elements, division, applicable working couple, basic operation parameters and possibilities realized solar refrigerating systems. Alternative part smoothing - out practical page. Elaboration project proposal wiring solar refrigerating system with absorbing period, about refrigerating achievement 6 kW and processing constructional proposal personal refrigerating troop. In fine will basic technical economic juxtaposition solar refrigerating troop with compressor refrigerating period

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The thesis describe high-pressure cooling system and present experiment, when is using this cooling technology for turning cylindrical workpiece to long-turn machines. Workpiece manufactured using high-pressure cooling system is compares with Workpiece manufactured using low-pressure cooling system. Results are analyzed, evaluated and plotted in a single graphical relationships. The thesis is completed the analysis, discussion and recommendations regarding the using of high-pressure cooling.

Master of Science / Department of Architectural Engineering and Construction Science / Fred L. Hasler / This paper discusses the advantages of applying a utility centralized chilled water system as the district cooling choice for facilities in the high-density urban areas of China and how it will influence China’s development in the next decades. Presently, the Chinese government is trying to contribute to the world’s energy-saving goals as well as determine its sustainable development framework. As air pollution has become one of the main problems in China, indoor air quality (IAQ) is likely to gain priority as a building design consideration in the future. Consistent with this fact, this paper proposes an optimum HVAC system for cooling purposes to the Chinese government. Compared to unitary HVAC systems, the centralized HVAC system has significant advantages in system efficiency, energy reduction and cost savings and can, therefore, be a better choice. Furthermore, the paper will focus on the centralized chilled water system and demonstrate why they better match the development model in China. The application of the system in high-density urban areas will also be discussed. Due to a lack of understanding that the energy consumption of unitary systems, the first comparison presented is between unitary HVAC systems and centralized HVAC systems in individual buildings. The comparison presented will focus on the energy-saving benefits of the centralized HVAC system in individual buildings and its contribution to sustainable development. Consequently, prescribing a centralized chilled water system as a utility district cooling system and applying a centralized chilled water system to each individual building in the highdensity urban areas will be compared. Cost savings, including initial cost and life cycle cost, are the metrics used in this comparison. Additionally, energy consumption and system reliability will be explored in determining which model will be more appropriate for China's development. The paper concludes that the centralized chilled water system should become the mainstream in the high-density urban area in China. Several recommendations are also made to the Chinese government on setting up utility centralized chilled water systems.

Programa computacional em Matlab-Simulink para simular o comportamento do sistema de arrefecimento de veículos comerciais (vans, ônibus e caminhões) equipados com motores diesel. O programa está embasado em uma modelagem matemática que visa caracterizar o funcionamento dos componentes principais do sistema: motor, radiador, termostato, by-pass e bomba d\'água. Tendo como entrada dados característicos do veículo em estudo, o programa computacional fornece a distribuição de temperatura ao longo do tempo para o líquido de arrefecimento - parâmetro preponderante em uma análise do sistema. Os resultados da simulação permitem aos projetistas prever a atuação do sistema de arrefecimento em diversas condições, o que possibilita a realização de um número menor de testes de pista. Os benefícios de um sistema de arrefecimento projetado adequadamente podem ser notados em relação à economia de combustível, ao aumento de desempenho e à redução do desgaste de determinadas peças do motor e da emissão de poluentes. / A software was developed having Matlab-Simulink as basis and it simulates the behavior of the cooling system in commercial vehicles (vans, bus and trucks) equipped with diesel engines. The program is based on mathematical models to describe the main components of the system: engine, radiator, thermostat, by-pass and water pump. Having as input data the features of the vehicle in studied, the software supplies the cooling fluid temperature distribution during certain time - preponderant parameter in the analysis of the system. The results of the simulation allow the designers to foresee the cooling system performance in several conditions, decreasing the number of track tests. The benefits of an adequate designed cooling system project can be noticed considering fuel economy, performance improvement and decrease of wearing of specific parts in the engine as well as pollutant emissions.