基于动网格的往复式压缩机进气阀数值模拟

Numerical Simulation of Suction Valve of Reciprocating Compressor Based on Dynamic Meshes

为了研究往复式压缩机进气阀的多物理场变化特点,运用CFD和动网格技术模拟进气阀从膨胀到进气的整个过程。通过模拟流场计算阀片壁面上的压力,然后求解阀片运动方程,获得了阀片的运动规律以及瞬时温度场和流场。研究结果表明:阀片开启后,气缸内各物理量分布呈现明显的不均匀性,局部压力和温度持续下降后再逐渐升高;当曲柄转角为60°和80°时,分别有最大温差17.1℃和最大压差3 930 Pa,模拟的阀片开启区域为[53.2°,219.5°],与理论结果[56.0°,220.0°]很接近,验证了数值模拟方法的正确性;阀片对升程限制器和阀座的最大撞击速度分别为2.3和1.3 m/s,为确定阀片的冲击载荷提供了基本数据。研究结果对于全面认识流体流动细节、阀片运动规律和压缩机的工作性能具有重要意义。

To study the multi-physics variation characteristics of the reciprocating compressor suction valve, CFD and dynamic mesh technology are used to simulate the whole process of the suction valve from expansion to suction. The pressure on the wall surface of the valve plate is calculated by simulating the flow field. Then, the equation of motion of the valve plate is solved. The motion law of the valve plate and the instantaneous temperature field and flow field are obtained. The results show that after the valve is opened, the distribution of physical quantities in the cylinder is non-uniform. Continue decrease and then gradual increase of local pressure and temperature is observed. When the crank angle is 60° and 80°, the maximum temperature difference of 17. 1 ℃ and the maximum differential pressure of 3 930 Pa is respectively obtained. The simulated valve opening area is [ 53. 2°, 219. 5°], which is quite close to the theoretical result [ 56. 0°, 220. 0°], verifying the correctness of the numerical simulation method. The maximum impact speed of the valve plate on the lift limiter and seat is 2.3 and 1. 3m/s, respectively, providing the basic data to determine the impact load of the valve. The study results are of great significance for a comprehensive understanding of detailed fluid flow, valve motion and compressor performance.