A Study of Engine Bearings Friction Loss Reduction Under Hydrodynamic Lubrication Conditions 2022-01-0324
The mechanical loss reduction of the bearing reduces the fuel consumption of the engine, which can help realize a sustainable society. Thus, a bearing friction reduction technique has been studied. There have been many studies related to friction-reduction techniques for mixing and boundary lubrication. However, there are few studies on hydrodynamic lubrication, and the main methods have been related to changing the low-viscosity oil and bearing size. In driving passenger cars in urban areas, the lubricant condition of the engine bearings is largely dependent on hydrodynamic lubrication. Therefore, the power loss under this operating condition cannot be ignored.
In this study, the reduction of the friction loss under hydrodynamic lubrication was focused. A method for reducing the shear resistance of oil was examined and its effect was confirmed through experiments and calculations. The test was conducted using a static load-bearing tester designed for the friction measurement under hydrodynamic lubrication. To further reduce this loss, it was confirmed that the properties of the bearing surface should be oil-repellent rather than lipophilic. Furthermore, the swell shape of the bearing surface showed good results parallel to the direction of rotation. Bearing roughness lowers friction because of its fine surface.
Citation: Koushima, M., Tamura, T., and Itoigawa, H., "A Study of Engine Bearings Friction Loss Reduction Under Hydrodynamic Lubrication Conditions," SAE Technical Paper 2022-01-0324, 2022, https://doi.org/10.4271/2022-01-0324. Download Citation