隔膜压缩机三指数母线膜腔轮廓优化设计

摘要

隔膜压缩机的膜腔轮廓决定了压缩机的流量和膜片的应力分布.膜片破裂实例表明膜片径向应力过大是膜片破裂的主要原因,因此利用薄板大挠度理论对膜腔轮廓进行优化设计时,应以径向应力不超过许用应力为设计原则.对如今广泛使用的单指数母线膜腔轮廓进行了优化计算,并分析了该轮廓的特点和不足,在此基础上提出了三指数母线膜腔轮廓及其优化算法.两种轮廓的优化计算结果表明,在相同膜腔半径、相同膜片材料及膜片内应力均达到许用应力条件下,三指数母线膜腔容积相比单指数增大10.1％;在相同膜腔半径、相同膜腔容积及相同膜片材料情况下,三指数母线下的膜片最大径向应力相比单指数降低13.5％,膜片中心区域最大径向应力降低18.3％.%The flowrate and the stress distribution in the diaphragm are determined by the cavity contour in the diaphragm compressor.The practical application showed that the exceeded radial stress was the main reason of the diaphragm failure.To guarantee the radial stress not exceed the allowable stress should be the design principle of diaphragm compressor.In this paper,the optimization algorithm for the traditional generatrix of cavity contour was presented and the characteristics of traditional generatrix were discussed.Furthermore,a new generatrix of cavity contour and its optimization algorithm were presented.The comparison results of two different generatrix showed that the cavity volume of new generatrix was 10.1％ larger than that of traditional generatrix with the same design parameters.The maximal radial stress of the diaphragm in the cavity contour with new generatrix was 13.5％ less than that with traditional generatrix and the maximal radial stress in the center area decreased by18.3％.