转子压缩机滚动活塞角速度的计算方法比较

Comparison of Calculation Methods of Rolling Piston Angular Velocity of Rotor Compressor

转子压缩机滚动活塞角速度的计算对于压缩机的动力学分析至关重要,其计算方法有多种。近年来提出的简化解析式法及平均值法具有计算简便的特点,但其准确性方面却鲜有研究。以滚动活塞角速度的精确计算方法——迭代法为对比标准,利用MATLAB软件编写程序研究了两种方法(简化解析式法及平均值法)在计算活塞角速度时的计算精度,并研究了压缩机润滑油粘度、主轴转速、滚动活塞与气缸端盖间隙、滚动活塞与偏心主轴间隙等参数对活塞角速度的影响。比较结果表明:平均值法计算的活塞角速度为一个大于精确值的恒定值,且恒定值与精确值之间的误差较大;与平均值法相比,简化解析式法计算的活塞角速度不仅变化趋势与精确值一致,且计算精度也得到很大提升。迭代法由于计算准确可用于压缩机活塞性能参数的理论仿真,而简化法和平均值法虽然计算精度不高,但其简单的公式可用于压缩机活塞的结构设计。这为滚动活塞角速度计算方法的使用提供了参考。

There are many methods to calculate the rolling piston angular speed of a rotor compressor,for it is essential to analyze kinetics of the compressor.Though the simplified analytic method and mean value method,which have been proposed in recent years,have the advantage of easy calculation,there are few studies on accuracy of these two methods.Selecting calculation method(iteration method)of rolling piston angular speed as the comparison criterion,this paper investigates calculating accuracy of the two methods(simplified analytic method and mean value method)using MATLAB software when they are used to calculate the piston angular speed,and the effects of some parameters on piston angular speed,such as lubricating oil viscosity,mainshaft speed,clearance between rolling piston and cylinder end cap and that between rolling piston and eccentric shaft.The results indicate that the piston angular speed obtained by mean value method is a constant value,which is largely bigger than the precise value.The simplified analytic method not only gets the same piston angular speed's variation trend as results through the iteration method,but also has higher computational accuracy compared with mean value method.The iteration method can be used to take precise theoretical simulation of compressor piston performance parameters.Though simplified analytic method and mean value method do not have fair computational accuracy,they can be used for compressor piston structure design due to their simple equations.This study provides references for using calculation methods of the angular speed of rolling piston.