Abstract
As internal combustion (IC) engines evolve under the pressure of environmental concerns, strict emission norms and growing expectations of customers, the need for inexpensive, fast, robust and reliable simulation tools in engine development is becoming more and more evident. Significant part of engine power losses arise from friction losses at piston-cylinder and ring-cylinder contacts. Therefore, dynamic simulations of the piston group (cylinder, piston, piston rings) are of great importance. The aim of this paper is to present a finite element based simulation model of in-cylinder dynamics, contact properties of the piston group and friction calculation methods. Results of different sets of calculations are shown in order to underline the capabilities of the model. Coulomb and Stribeck friction models are compared by calculating friction power losses at various engine speed settings. Studies are carried out to show the effects of a) gas pressure, b) bore distortion and c) piston ring width on frictional properties of the piston group.
Keywords: IC engine, piston group, dynamic simulation, friction model, Stribeck curve