Abstract
Keywords Diesel Engine, Valve Train, Valve Rotation, Valve Spring, Valve Seat Wear
Abstract In this paper we present the effects that valve train design parameters and operating conditions have on the valve rotation properties of a diesel engine. Rotation of intake and exhaust valves is very closely related to the long term durability of diesel engines. If the valves do not rotate even at a rated engine speed, it causes the uneven wear of the valve seat and valve head contact area, which eventually shortens the engine life. Because the rated speed of a diesel engine is relatively lower than that of a gasoline engine, the operating condition of a diesel engine produces tough environment for valve rotation. Therefore, the valve rotation is an important problem, which should be solved in the early stage of engine development. In this study, we developed a new technique to measure the valve rotation and shaking motion simultaneously using three proximity sensors. Valve rotating properties of a diesel engine were measured under various engine operating conditions. A computer program was also developed to simulate the valve rotation phenomena. Using the simulation program and test results, effects of valve train design parameters and operating conditions on the rotation properties were investigated.