Research On Thermal Properties In Liquid-Solid Lubrication

Practically, solid particles exist inevitably in pure liquid lubricant. And the particles will have a great influence on the lubrication and thermal properties of lubricant. The performance and the life of machine parts will vary with the change of the lubricant characteristics. So the study on the liquid-solid lubrication not only has important meanings to lubrication theory, but also has great value in practice.The lubrication and the thermal properties of lubricant with the existence of solid particles are analyzed in this thesis. On the one hand, considering smooth surface, the characteristics of lubricant are discussed under different loads, particles' diameters and particles' shapes. Taking the effect of viscosity temperature of lubricant into account, the changes of the pressure and temperature of the liquid-solid lubricant are analyzed. A contact model, which provides a method to calculate contact temperature between the particle and the surface of the tribopair, is presented. On the other hand, taking surface roughness into consideration, the fluid pressure, temperature, friction force and other properties have been analyzed under different loads, velocities, particles and shapes of asperities. Subsequently, the squeeze effect of fluid, the heat transfer between the particles and the fluid are simulated by ANSYS.