Prediction of Temperature, Viscosity and Thickness in Oil Film Between Ring and Liner of Internal Combustion Engine 2000-01-1790

The temperature, the viscosity and the thickness in the oil film on the piston ring in internal combustion engines are predicted by using unsteady state two dimensional (2-D) thermohydrodynamics lubrication analysis, that is Reynolds equation and 2-D energy equation. The oil film temperature calculated using by unsteady state 2-D energy equation in which the heat generated from the viscous dissipation. The temperature distributions in the oil film are affected by the viscosity, the wall velocity and the oil film thickness and also the ring and liner surface temperatures, the convection and the conduction heat flow. The temperature of oil film increases with the increase of the engine speed for the viscous dissipation and there is an effect of unsteady term during near at the top dead center (TDC) and the bottom dead center (BDC). The viscosity by unsteady state analysis decreases with increase of the engine speed due to viscous dissipation. The oil film thickness by unsteady state analysis increases with increase of the engine speed as well as results by quasi steady state analysis.