余隙容积对微型高压压缩机容积效率的影响

Effects of Clearance Volume on Volumetric Efficiency of a Miniature High-pressure Compressor

余隙容积的合理设计是保证压缩机正常工作的必备条件。相较于传统的高压压缩机,微型高压压缩机体积小、结构紧凑,活塞行程短且高压级活塞的直径较小,因而其工作性能对余隙容积更为敏感。为研究余隙容积对微型高压压缩机各级工作腔容积效率的影响,在微型高压压缩机关键结构参数和压力参数的基础上,结合能量和质量守恒定律、气阀运动以及活塞运动规律,搭建了工作腔热力学仿真模型。分析不同余隙容积下各级工作腔内气体压力、质量的瞬态变化过程,得出各级工作腔内容积效率的变化规律,从而为微型高压压缩机缸体和气阀关键结构参数的设计和优化提供指导意义。

The reasonable design of clearance volume is necessary to ensure the normal operation of compressor. Compared with the traditional high-pressure compressor,miniature high-pressure compressor holds the features of compact size and light weight. The piston stroke and diameter of the high-pressure piston are small,which result in its performance more sensitive to clearance volume. This study focuses on analyzing the effects of clearance volume on volumetric efficiency of each stage in miniature high-pressure compressor. Thermodynamic process models are built based on structural parameters,energy conservation law,mass conservation law,valve motion and piston motion. Transient changes of gas pressure and mass in working chambers with different clearance volumes are analyzed. The variation rule of volumetric efficiency of each stage is discovered. This work can provide guidance for the design and optimization of key structural parameters of cylinders and valves in miniature high-pressure compressor.