Research On Thermal EHL Of Rolling Bearing Based On Multigrid Method

Macroscopic properties including carrying capacity, strength, reliability and service life of rolling bearings depend mostly on microscopic characteristics of the interface between the rolling element and raceway. However, calculation of the macroscopic properties is still mostly based on modified Hertz Contact Theory without considering the lubrication, thermal and inhomogeneous material. It is difficult to accurately describe the contact interface behavior for the bearing of aviation transmission under heavy load and high speed. Therefore, the thermal EHL, lubrication and friction characteristics research of rolling bearing are carried out, which will lay a certain theoretical and practical foundation for improving the reliability and life.Firstly, isothermal and thermal EHL lubrication of the line contact are solved by using the multi-grid and scanning method, steady convergence solutions are obtained, and thermal, slide to roll ratio, starvation effect on the EHLare analyzed.Secondly, numerical simulation of the point contact is rearched, and the pressure, film thickness and temperature are obtained under EHL and thermal EHL based on multi-grid method combining with low Gauss-Seidel relaxation iterative method, Jacobi iteration method dipole. Meanwhile, load parameter, material parameter, speed parameter and thermal effects are discussed on EHL performance of the point contact.Again, thermal EHL analysis of deep groove ball bearing with large oval is conducted, and pressure, film thickness and temperature in the contact area of the rolling element and inner ring raceway are obtained in the application of thermal EHL theory of elliptical contact. Moreover the effect of working conditions, geometry and lubrication parameters are analyzed on the thermal EHL of deep groove ball bearing.Finally, the ball-disc friction experiments of large slide to roll ratio are tested, and friction coefficient under different load and speed is measured. Furthermore, the effects of speed and load on friction coefficient are analyzed, and the results show high reliabity of theoretical research.