Theoretical and Experimental Evaluation of Diesel Engine Derating Effect on Its Life Time

The mathematical model for predicting diesel lifetime has been developed. Equations that can be used to determine a relative rate of engine details damage accumulation depending on design, adjustment parameters and load from the objects of application are proposed. These equations take into account inertial loads due to engine speed change, gas pressure in the combustion chamber, heat change and engine parts wearing. Equation for determining the rate of damages accumulation caused by heat changes is proposed. Numerical and experimental studies were carried out, which made it possible to predict a change in the diesel engine lifetime due to a change in its operation modes during adaptation for an industrial tractor. The study results can be used to create diesel engines derated modifications and to develop similar methods for predicting internal combustion engines, which differ in power and objects of application, life time. The calculation methodology, developed on basis of the proposed mathematical model, is used in Chelyabinsk Tractor Plant and South Ural State University at the development of industrial tractor diesel engine modifications.