A Rapid Method of Numerical Calculation for Oil Film Temperature in Engine Bearings

In the design and analysis of engine bearings for automobiles, the elastic deformation of bearing surface due to high pressure and temperature of oil film affects significantly on the bearing characteristics. Thermo-elasto-hydrodynamic lubrication analysis (TEHL) is usually used to consider such effects, but a large amount of calculation time is needed to obtain the numerical solution of oil film temperature by solving the conventional type of 3-dimensional energy equation in TEHL. This paper describes a rapid method of numerical calculation of oil film temperature in engine bearings. In this modeling, it is assumed that the temperature distribution in the oil film thickness direction takes the parabolic form. Under such an assumption, averaging the 3-dimensional energy equation over the film thickness, the 2-dimensional energy equation is newly obtained. The numerical solutions of oil film temperature based on the 2-dimensional model are compared with the solutions based on the 3-dimensional model. It is confirmed that the calculation time is remarkably reduced to obtain the oil film temperature with an allowable accuracy. Moreover, the predicted oil film temperature by the 2-dimentional model is compared with measured data, and the good agreement is seen between them.