Computational Analysis of Piston-Ring Wear and Oil Consumption for an Internal Combustion Engine

This paper presents the computational analysis of piston ring wear and oil consumption for an internal combustion (IC) engine. Two computational models, piston-ring wear and oil consumption, are employed to simulate the results for this analysis. Both instantaneous and transient results are discussed. The piston-ring wear model, namely WEAR, is built on the fundamentals of mechanical and adhesive wear mechanism; while the oil consumption, namely OILCONSUME, is on the fundamentals of oil vaporization and upper-ring gap oil reverse flow mechanisms. The two models are integrated with two external engine simulators: the Ford Motor Company General Engine SIMulation (GESIM) of the Ford Motor Company, and the Cylinder kit Analysis System for Engines (CASE) of the Michigan State University Engine Research Laboratory. An objective of this analysis is to understand how the engine operation condition impacts the piston-ring wear and the oil consumption per engine cycle basis. Also, it is to understand how the piston-ring wear affects the oil consumption and other engine mechanisms on a long time basis. A virtual Ford 4.6L-V8 engine has been tested on various engine speeds and loads to produce the computational results. The results show that the engine load and the engine speed play significant roles, individually and collectively, on the engine performance. The results also show the dependence of the oil consumption and the blow-by on the piston-ring wear over long-time engine run. The instantaneous and transient simulations have provided useful insights on the relation between the piston-ring wear and the oil consumption mechanisms in an IC engine.