A Study of Crankshaft Vibration Mechanism in Operation : Visualization of the Vibration Mechanism by means of Time History Response Analysis is Consideration of Nonlinearity of Oil film

Abstract

The vibration behavior of the crankshaft in operation is complex to simulate because there are many contributing factors, some of which are varying, oil film stiffness and damping, coupled vibration of the rotating crank train and cylinder block. This paper describes a new method of analyzing the nonlinear vibration of rotating crank train, in which calculations are made of using nonlinear equation of motion. This method uses stiffness and mass matrices of the component parts, which have been extracted from the finite element model using in-house software. The coupled vibration of the rotating crankshaft and cylinder block is calculated by means of time history response analysis, in sonsideration of the non-linearity of the oil film stiffness, damping and friction. The accuracy of this calculation technique was demonstrated by comparing the calculated results with the actual vibration measured with LASER equipment.