Study On The Performance Of Radial Over-Expanded Gas Wave Refrigerator

Gas Wave Refrigerator (GWR) is a new kind of refrigeration devices by usting the principle of gas expansion. In this paper, the Radial Over-Expanded Gas Wave Refrigerator is a main research object. The flow characteritics of its inner flow field and its refrigation process are analysed with the method of numerical simulation and the theory of gas dynamics. These results have reference value for improving the refrigeration efficienty and optimizing the refrigeration process. The main working contents are shown as follow:(1) The working principle of GWR is discussed with the theory of shock wave. The calculation formula of shock wave is deduced. The formation and movement of gas wave is analysed. An ideal wave pattern is plotted. At last, the way to match the ports of GWR is discussed in detail.(2) A numerical model of Gas Wave Refrigerator with single channel is simulated. The movement of shock wave and contact surface is shown. The relationship between included ange of nozzles and position of shock wave is analysed. Simulation results show that the best reasonable matching position can be got when half of the channel is connected with outlet nozzle and the shock wave reaches the end of the channel.(3) A thermomechanical analysis of refrigeraton process is carried out. The graphical workflow charts of External-Circulation GWR and Over-Expanded GWR are plotted respectively. The relationship between refrigeration efficiency and operating parameters is studied. Results show that the changes of temperature, pressure and rotation speed have an effect on the refrigeration efficiency and temperature difference.(4) A2-D numerical model of Gas Wave Refrigerator is created. The relationship betwwen refrigeration efficiency and structure parameters is studied by using the method of numerical simulation. Simulation results show that the refrigeration efficiency is influenced by the scale of nozzles and the length of channels. The working performance of GWR can be optimized by usting canted nozzle and forward-curved channel.