将含油结合面刚度分为固体接触刚度和液体油膜动态刚度2个部分,且2个部分为并联连接.利用接触分形理论,建立含油结合面固体法向接触刚度和结合面实际固体接触面积的关系模型;在此基础上,结合面间充满油的面积即为名义接触面积和固体实际接触面积之差,利用平均流动的广义雷诺方程,建立多孔含油材料固定结合面液体油膜法向动态刚度模型;两者并联即可获得含油结合面综合动态刚度模型.通过仿真计算和前期试验结果对比,验证该建模方法的正确性.研究表明:结合面间加入润滑油介质可以有效地提高结合面刚度;而利用多孔含油材料,即自润滑材料,是实现在结合面间加油的有效方案.
The stiffness of oily interfaces can be divided into two parts, solid contact stiffness and liquid oil film dynamic stiffness; meanwhile the two parts are shunt connection. Using fractal theory of contact, the model for normal solid contact stiffness of the oily interface was established, which is related to the area of actual solid contact surface; on this basis, the area of the oil-filled contact is the difference between nominal contact area and actual solid contact area, and the model for oil film normal dynamic stiffness of porous oily material fixed joint interface was set up based on the average flow of generalized Reynolds equation. The model for normal comprehensive dynamic stiffness both can be easily obtained considering the shunt relationship. Through simulation and comparing to previous experimental results, the correctness of the modeling method was verified. Results show that the stiffness of joint interfaces can be effectively improved with oil media filled into the interface. In addition, using of oily porous material, that is, self-lubricating material is proved to be an effective proposal for oil-filling between the joint interfaces.