Thermal Design And Optimization Of Structural Parameters On Two-Dimention Centrifugal Compressor For HTHP

Energy and environmental problems are great social concerns nowadays which the countries all over the world face. With quickening of the cities and economy development speed,China will face great pressure of energy resource supply and environment protection for a long time.Heat pump technology ,it has been an important technology measure to reduce energy consumption of the fossil energy resource and environment pollution.Development of the technology of high temperature heat pump(HTHP) with centrifugal compressor, have important meaning to area heating of the northern urban of our country and other heating field. Centrifugal compressor is the key part of the centrifugal compressing type heat pump. It's operational efficiency, operating mode range and security performance directly influence the performance of the whole heat pump. The impeller is thought to be the most important and complicated part in centrifugal compressor. Transformation of the shaft mechanical energy to the pressure energy of the compressed gas is realized in the impeller. It is the only way of improve the gas energy. In all words, correct design of the centrifugal compressor and numerical study of the related flowfield of impeller have important meaning to optimize the performance of the centrifugal compressor.The contents of this book are shown as followings.Firstly, high temperature refrigerant R123 and R134a are initially selected for the centrifugal compressor. The two refrigerants R123 and R134a have different property in environmental protection and safety; and several countries government have different attitude on them. The result is that R123 is more suitable than R134a for high temperature pump centrifugal compressor set, so the dissertation decides refrigerant R123 as a good choice.Secondly, theory of one-dimensional flows is adopted to introduce the principle of the centrifugal compressor structural design in this dissertation, and building structural design model for the two-dimension centrifugal compressor adopting refrigerant R123, including impeller, diffuser, and volute. It provides a basis for the compressor sample.Lastly, Gas energy equation educed from the first law of thermodynamics points the last part mechanical work is idle work, and it is the loss we usually say. According to the second law of thermodynamics, the loss is unavoidable, and is only reduced. So this dissertation builds energy loss model of the centrifugal compressor from energy loss point. The loss include the impeller entry separation loss, the friction loss, the leak loss, the wheel resistance loss, leafless diffuser loss, the curve loss and the volute loss. To reduce the loss, the dissertation analyzed and optimized the main loss in the model, and that can increase the centrifugal compressor efficiency.