Study On Steam Compression Refrigeration With Wave Rotor

With the emergence of environment problems,such as the destruction of the ozone layer and global warming,it is restricted to the use of the traditional refrigerants.This is an urgent global problem to look for suitable and alternative refrigerants.Water is the ideal environmental protection alternative refrigerant,which is widespread in nature,non-toxic,pollution-free,high safety.But the refrigeration cycle that use the water to act as the refrigerant would have shortcomings that higher exhaust temperature,bigger pressure ratio and larger volume flow,compared with the common refrigeration cycle,put forward higher requirements to the compressor.In this paper,the wave rotor is used for water vapor compression refrigeration,which is replaced the last stage of the two-stage compression refrigeration cycle and the condenser.This paper establishes a system diagram of the wave rotor refrigeration cycle,analyzes its working principle,conducts a detailed study of the three-port wave rotor which is the key device of the system,analyzes the formation and movement characteristics in the three-port wave rotor of internal shocks and expansion waves,sets up the refrigeration cycle's thermodynamic model of the wave rotor based on the parameter changes of the airflow before and after the shock wave.For preferably optimize the refrigeration cycle's properties,this paper builds the three-port wave rotor's ideal wave diagram,designs the wave rotor's size applying the one-dimensional unsteady analysis method of gas dynamics,makes numerical simulation by FLUENT software.This paper calculates the refrigeration cycle's thermal force of the wave rotor and the two-stage compression that compared with the singlestage compression refrigeration cycle,and studies the effects of the wave rotor pressure ratio and the evaporation temperature on the refrigeration coefficient of the cycle,the compressor exhaust temperature and the system power consumption.The internal flow field is analyzed based on the numerical simulation results of FLUENT software,and the distribution law of fluid pressure and temperature in the threeport wave rotor is obtained.The performance analysis of the wave rotor refrigeration cycle shows that in the air condition refrigeration cycle of the wave rotor compared with the singlestage compression refrigeration cycle compressor pressure ratio can be reduced by 55.56%,the discharge temperature of compressor can be reduced by 42.51%.The cooling coefficient increases first and then decreases with the increase of wave rotor pressure ratio,in the wave rotor pressure ratio 2.25 the refrigeration coefficient epsilon increased by 8.67%,to 4.95.Compared with the two-stage compression refrigeration cycle,the refrigeration coefficient of the wave rotor refrigeration cycle increases with the increase of evaporation temperature.When the evaporation temperature is greater than 4?,the refrigeration coefficient of the wave rotor refrigeration cycle is greater than the two-stage compression refrigeration cycle,and the wave rotor refrigeration cycle is suitable for the working conditions with higher evaporation temperature.