Research Of Numerical Simulation And Application Of Line Contact Wear

Wear of mechanical parts has been one of the research focuses in the field of tribology. Smooth wear is the most common form of composite wear. Because this kind of wear has the feature of slow gradualness, the impact brought by the smooth wear to the properties of mechanical systems is often neglected as compared with unexpected wears. But it has great hazard.At present, domestic and foreign research on wear is mainly focused on experimental research. And it has got a lot of achievements. However, experimental research requires a lot of manpower, material and financial resources, and the conclusions obtained have strong application conditionalities. On the other hand, tribology researchers have been committed to apply the research achievements of tribology to engineering design. But the effect is not obvious, because the tribology theory has not achieved the being applied level in engineering design as classical mechanics theory. It is even very difficult for the classical wear theory to be directly connected with wear life prediction, wear dynamic process monitoring and abrasion resistance design in engineering projects as hoped.As the development of tribology,'computational tribology'has been showing its strong vitality increasingly. Computational tribology is to apply the numerical simulation technology to the study of wear, in order to predict the wear life of parts and direct the optimal design of abrasion resistance for friction pairs. Numerical simulation is a new technology combined with discrete mathematics and computer technology. It has been widely applied in engineering and achieved excellent results.In this paper the wear numerical simulation model will be established through making numerical simulatiing for the wear of friction pairs of line contact parts, taking factors such as temperature, pressure, etc. into consideration. Then by introducing the reliability theory into the numerical simulation model, a method will be provided in order to predict the wear life of line contact parts and direct the optimal design of abrasion resistance for friction pairs.The main research contens of this paper are:(1) The establishment of contact modelIn order to establish the mathematical model for wear simulation, the pressure distribution law of the Hertz contact area has to be known at first. Then the contact pressure of the Hertz contact area has to be solved in order to lay the foundation for the subsequent establishment of the simulation model.(2) Research on the material wear rateBy analysing various factors affecting wear of materials comprehensively, and selectting experimental methods that have broad scope of applications, the general formula for the material wear rate of line contact parts will be obtained through experiments and methods such as experimental data processing, parameter correction, etc., taking consideration of the factors such as pressure, temperature, lubrication, etc.(3) The establishment of the simulation model for the wear of line contact partsBased on the basic idea of numerical simulation, the continuous wear process of a single part will be made discrete, and the dynamic process will be made quasi-static in each discrete element. Meanwhile, the wear displacement situation will be taken into full account in the wear process as the basis for the subsequent wear claculation.(4) The establishment of the simulation algorithm of the reliability estimation for the wear lifeSo far, fixed values are still being generally used for the prediction of wear life. But it is not scientific. The wear life of mechanical systems has significant probability features. By using the probability theory of Monte-Carlo method, the algorithm of the reliability estimation of the wear life will be established and the general software for the wear probability life will be prepared, taking the parameters such as load, velocity, etc. and the random distribution features of the wear process of gradual onset into consideration.(5) The establishment of simulation models and the simulation analysis for typical line contact partsBy using the established general wear simulation model, the wear numerical simulation and probability life estimation for the cam mechanism systems, bearing mechanism systems and gear mechanism systems will be established in order to support the further optimal design in abrasion resistance.This paper is supported by the project of National Natural Science Foundation of China—"Research of theory and methods for design of probability wear life of systems based on numerical simulation"(Project Number:50375022).