关键词: 真实气体效应, 气波制冷机, 波系运动, 制冷效率, 能量传递

Abstract: The gas wave refrigerators were usually designed and operated based on the ideal gas model. However, as the operating parameters of natural gas reservoirs progressively towards higher pressure and higher pressure ratio working conditions, the real gas effect cannot be disregarded any more. In this study, a two-dimensional computational model of a double-opening gas wave refrigerator (GWR) utilizing a multi-parameter BWR equation of state was established, focusing on high-pressure ratio conditions using the Yaha natural gas reservoir in the Tarim Basin of Xinjiang as the working medium. The influence of the real gas effect on the wave dynamics and energy transfer processes in the GWR with discontinuous boundary conditions was thoroughly investigated. The numerical results showed that the wave dynamics of the ideal methane gas and the real natural gas were similar under different operating conditions. However, it was observed that the compression waves and expansion waves in real natural gas obviously lagged behind the ideal methane gas. The low-temperature real natural gas was completely discharged earlier than ideal methane gas and the difference between them gradually increased as the pressure ratio gets higher. Specifically, the length of the LT outlet could be shortened by 56.5% at a pressure ratio is 6. Furthermore, the temperature of the real natural gas being discharged was lower than that of the ideal methane gas, so the refrigeration efficiency of isentropic expansion of the real natural gas would be improved compared with the operation in ideal methane gas. The research results on the real gas effect elucidated the mechanism of wave dynamics and energy transfer, providing support for the optimization of GWR design in natural gas ground engineering applications.

Key words: real gas effect, gas wave refrigerator, wave dynamics, refrigeration efficiency, energy transfer