Design of Internal Combustion Engine Piston Based on Skirt Lubrication Analysis

Many piston parameters and the profile of piston skirt should be optimized in order to get the best lubrication. To attain optimized parameters, a lubrication analysis of piston skirt was carried out. After having investigated the real condition, a numerical lubrication model was established and computer programs were worked out to simulate the performance of skirt, and every parameter can be modified to optimize the whole skirt parameters. In addition, an equipment to measure the oil film thickness between piston and bore was developed to verify the numerical simulation model. Because various parameters, like radial clearance, piston surface profile, piston pin offset, and skirt length, made experiments too difficulty to implement, the program simulation become exercisable and economical method. Through the simulation a group of optimized piston parameters could be obtained easily.