接触式机械密封端面微凸体变形特性研究

Research on deformation property of end face asperity of contact mechanical seals

依据分形理论,考虑摩擦作用的影响,分析了接触式机械密封摩擦副端面微凸体的变形特性;得到了端面微凸体临界弹性变形微接触面积和临界塑性变形微接触面积,端面间微凸体弹性接触面积、弹塑性接触面积、塑性接触面积以及弹性接触面积比的数学表达式.用数值仿真方法得出了GY70型机械密封摩擦副端面间的弹性接触面积比.研究表明,弹性接触面积比随着分形维数的增大先增大后减小,随着特征尺度系数的增大而减小,随着端面摩擦因数的增大而减小.对于机械密封摩擦副接触端面,存在一个最优的分形维数值,使得弹性接触面积比最大,摩擦副端面间的磨损最小.对于GY70型机械密封,其软质环端面最优分形维数在1.6左右.

＂Faking account of the influence of friction, the deformation property of the end face asperity of contact mechanical seals was analyzed by fractal theory. The mathematical expressions of the critical elastic： deformarion micro-contact area, critical plastic deformation micro-contact area, elastic contact area between end-faces, elastic-plastic contact area, plastic contact area, and elastic contact area ratio, were obtained. The elaslic contact area ratio between the end faces of GY70 mechanical seal was also obtained by numerical simulation. Research resuhs indicate that elastic contact area ratio increases at first and then decreases with the increase of fractal dimension, decreases with the increasing of characteristic length scale, and decreases with the increasing of end-face friction factor. There exists an optimum fractal dimension for the contacting end-face of friction pair, corresponding to the maximum elaslic contact area ratio and minimum abrasion between the end faces of friction pair. The optimum fractal dimension of the soft ring end-face of GY70 mechanical seal fractal dimension is about 1.6.