A Novel Approach to Reduction of Frictional Losses in a Heavy-Duty Diesel Engine by Reducing the Hydrodynamic Frictional Losses

Abstract

An important parameter in the reduction of fuel consumption of heavy-duty diesel engines is the Power Cylinder Unit (PCU); the PCU is the single largest contributor to engine frictional losses. Much attention, from both academia and industry, has been paid to reducing the frictional losses of the PCU in the boundary and mixed lubrication regime. However, previous studies have shown that a large portion of frictional losses in the PCU occur in the hydrodynamic lubrication regime. A novel texturing design with large types of surface features was experimentally analyzed using a tribometer setup. The experimental result shows a significant reduction of friction loss for the textured surfaces. Additionally, the textured surface did not exhibit wear. On the contrary, it was shown that the textured surfaces exhibited a smaller amount of abrasive scratches on the plateaus (compared to the reference plateau honed surface) due to entrapment of wear particles within the textures. The decrease in hydrodynamic friction for the textured surfaces relates to the relative increase of oil film thickness within the textures. A tentative example is given which describes a method of decreasing hydrodynamic frictional losses in the full-scale application.