Three-dimensional thermohydrodynamic analysis of the effects of textured main bearing on lubricant density and viscosity in internal combustion engines

This paper is focused on the effects of the textured surface along with lubricant feed pressure and temperature variation to calculate the lubrication characteristics (viscosity and density) of the main bearings in internal combustion engines. In a three-dimensional numerical analysis simulation, a thermohydrodynamic model was developed, which considered the thermal effects of the fluid–solid interface components. In the analysis, the viscosity–temperature equation was used at different lubricant feed pressures and temperatures. By using color image segmentation methods, the density and viscosity contour on the two rotating walls (shaft and bearing wall) in the cavitation regions were quantitatively and qualitatively compared. The textured surface and lubricant feed pressure had significant effects on reducing the cavitation region over the shaft and bearing surface. Compared with the untextured bearing, the presence of texture over the bearing surface in the same temperature and pressure conditions increased the amount of total heat transfer to the lubricant fluid in the range of the maximum value of 73% and minimum value of 11%. Promoting the average heat transfer coefficient was a factor in reducing thermal stresses and high-temperature points in the rigid parts of the bearing system.