70 Prediction of the Dynamic Characteristics in Valve Train Design of a Diesel Engine 2002-32-1839

In designing new valve train system, it is useful to predict the complicated dynamic characteristics correctly by CAE simulation at the initial stage. In this paper, a modeling technique of mechanical system simulation and the simulation results about the dynamic characteristics of the diesel engine valve train are shown. From the measured results, it is found that the valve spring plays an important role in the dynamic characteristics of valve train. Based on the results, we propose a new model which use beam coupled the displacement and shearing stress and gap elements to express the valve spring. The model is proved very well to express not only the same-pitch valve spring but also the different-pitch valve spring. As a result, the prediction of the dynamic characteristics of the valve train provides a lot of effective data and hint for the developing valve train design of a newly designed diesel engine.