Dynamic Calculation And Simulation Of Internal-Combustion Engine Valve-Train System

As one important part of the engine, the performance of valve train decides the performance of engine. The study on the valve train dynamics model is one main question for study the engine. As the engine becoming more intensified and its speed increasing quickly, the development and application of new model valve train getting more and more urgently. When we towards various dynamics model at present, how to compare and comprehend the specialty and the serviceable range of these models, it needs farther development in the future.This dissertation investigates it on the basis of a host of reference, and combines the real situation of the subject, which is cooperation with the Dongfeng Research Institute. A comprehensive study pattern, the integration of analysis, test and manufacturing is applied to study on the valve train dynamics model with performance.Based on the geometrical relation between tappets and cams, universal formulas for mutual lift-range transition between flat based tappet, roller (or sphere) tappet and cone tappet are presented. According to the comparison among several dynamics analysis models, a single mass system model has been established for evaluation. A dynamics model based on Simulink is developed for valve-train system of diesel engine. Valve-train system has been dynamically simulated by the application of Simulink model.Multi-body dynamics is the most active research field of mechanics in lately twenty years. In this paper, vavle-train as the research object is studied based on the theory of multi-body dynamics. According to blueprint and topology structure of the engine, multi-rigid-body dynamics model is built by software MSC.Admas. According to the dynamics model, simulation and calculation are finished by software MSC.Adams. Dynamic parameters of the valve-train are gained. Through analysis of the result, influence of unbalanced valves, different valve gap and velocity peak value of valve on seat are introduced.It is concluded through the study of this paper, that the method of building multi-rigid-body dynamics model can analyze dynamics response of valve-train well and truly, and detailed dynamic stress result can be gained from simulation.