Thermal Elastohydrodynamic Lubrication of Line Contact Considering the Thermal Elastic Deformation

Abstract

By considering the radial thermal elastic deformation of line contact solid surface caused by lubricant temperature rise, a new numerical method is utilized to calculate the solution of thermal elastohydrodynamic lubrication (TEHL) in line contact. According to the theory of micromolecular mechanics, there is a relationship built up among the temperature rise, elastic modulus, pressure, Poisson’s ratio, and the material line thermal expansion coefficients. Then, the material line thermal expansion coefficients of lubricated contact surface are calculated; the radial thermal elastic deformation caused by lubricant temperature rise is obtained and modified. The lubrication results including pressure, film thickness, and temperature are calculated. Meanwhile, the radial thermal deformation, the circumferential and axial thermal stresses are calculated by considering radial thermal elastic deformation in the solving process. The effects of different loads and entrainment speeds on the maximum values of film pressure, radial thermal deformation and lubricant temperature rise, and the minimum value of film thickness are studied. It is shown that values of the deformation caused by temperature and the minimum value of film thickness are in the same order of magnitude; thermal elastic deformation has profound influence on lubrication performance and should not be neglected.