Study On The Effect Of Starvation And Surface Topography To Simple Sliding Thermal Ehl Behavior

In this thesis,the behavior of point contact thermal elastohydrodynamic lubrication(TEHL)with surface topography under different starvation condition is investigated experimentally and theoretically.The performances of TEHL with a surface scratch were studied.Thereafter the effect of oil starvation to the surface dimple with surface groove was simulated theoretically.At last the effect of cavitation width to the surface dimple phenomenon in elliptical contact was investigated.Firstly,the experiments were conducted using the scratched steel balls by an optical interference technique on a custom-made test rig.The interferograms were gathered with a light load and a heavy load,respectively,in fully flooded and oil starvation conditions and.The film thickness curve on the midplane was measured by a multi-beam intensity(MBI)software.The experiments were simulated theoretically by a multigrid method.In addition the effect of groove size is investigated as well.Secondly,aiming at the surface dimple phenomenon observed in the experiments,the effect of the oil starvation on the surface dimple,film thickness,pressure and temperature distribution in smooth and scratched contacts was explored and explained by “temperature-viscosity wedge”.At last,extending the circular contact into the elliptical contact,the effects of oil starvation on the surface dimple variation,the width of the inlet starvation region on the performance of oil film together with the surface scratch at different location were explored.