| With the development and extensive use of the technology of refrigeration and air conditioning, the traditional way of refrigeration has resulted in two severe problems concerned by people presently, which are the issues about energy and environment. The evaporative cooling has got more and more recognition due to its advantages of energy-saving and environmental protection.Research on evaporative cooling and its application is carried out in this thesis.A new heat and mass transfer mathematical model, based on basic principles, has been developed for thermal calculations of direct evaporative cooling(DEC) ,with preliminary analysis by analogy with the theory of cooling tower. Also experimental research on DEC is made,and the effect of various influencing factors are investigated. Empirical equations for coefficient of heat transfer and air resistance are achieved and detailed comparison has been provided for inorganic padding and organic padding.Simulation and theoretic analysis on indirect evaporative cooling are made based on an improved model. And also, a simplified model is established to satisfy the needs of engineering calculation.The two models have little deviation.Combined evaporative cooling with exsiting technologies,two new air-conditioning systems are established.The calculation and analysis for the performance in 15 typical cities show that the direct evaporative cooling used in air-cooled chiller unit can greatly reduce the energy consumption of air conditioning and improve the cooling capacity and COP.It can be widely used in China.In addition,a new liquid desiccant evaporative cooling air conditioning system(LDCS),based on the optimization combination of DEC and IEC, is constructed.Several aspects for LDCS,such as system performance and regulating control method, are investigated. The research of performance indicates that it has great potential and wide practicality.
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