船舶推进轴系轴径倾斜对轴承负荷的影响

Effect of inclined shaft on the shafting alignment

船舶推进轴系由于受轴承布置及运行时各种动态因素的影响,轴线会有一定程度的弯曲变形.轴承中轴径的倾斜会导致轴承油膜厚度的变化,从而使轴承压力分布产生变化,当局部压力超过轴承允许比压时,易产生轴承局部区域磨损,因此有必要分析轴径倾斜对径向滑动轴承润滑性能的影响.对实船推进轴系进行分析,利用有限差分法求解Reynolds方程,用FORTRAN及MATLAB编程分别对艉管前轴承、艉管后轴承及中间轴承进行计算分析.结果表明:当轴径倾斜时,油膜局部压力超过允许比压,随着倾斜角度变大,局部最大压力突变,最小油膜厚度减小,其位置也向尾端倾斜,从而使油膜压力和厚度分布等发生了较大的边缘效应.

Since propulsion shafting is affected by many dynamic factors of bearing arrangement and operation,the axis will have a certain degree of bending deformation. The inclined shaft leads to the change of bearing oil film thickness,so that the bearing pressure distribution changes. When the local pressure exceeds the allowable bearing pressure,it is easy to produce the local wear of bearing,so it is necessary to analyze the effect of misalignment on the lubrication characteristics of the journal bearing. The ship propulsion shafting is analyzed by using the finite difference method for solving the Reynolds equation,the intermediate bearing and the bearings before and after the stern shaft is calculated by making use of FORTRAN and MATLAB. The results show that when the shaft is inclined,local film pressure exceeds the allowable specific pressure; with the increase of the inclination angle,the maximum local pressure changes abruptly and the minimum oil film thickness decreases;its location moves to the stern,so that the oil film pressure and thickness distribution changed greatly.