Effects of centroid bias on piston secondary motion

During the operation of the reciprocating engine, the piston will have a secondary motion due to the existence of the gap between the piston and the cylinder liner. Piston knock is one of the main excitation sources of diesel engine noise. The presence of second-order motion causes the piston to knock the cylinder liner periodically, which causes the surface vibration of internal combustion engine and radiates noise outwards In order to improve the sound radiation field of diesel engine, this paper uses AVL-Excite simulation software to establish a simulation model of piston secondary motion, and simulates the piston secondary motion. Get the law of this motion,then compare and verify it. Then by changing the centroid offset of the piston, the influence law of the centroid bias of the piston on the second-order motion is analyzed. Keywords: internal combustion engine, piston knock, second-order motion