Analysis And Optimization About The Valve-train Of High-speed Gasoline Engine

As the control mechanism of the intake and exhaust, the valve-train can open andclose in accordance with the requirements of the order and process of each cylinder,supplies the fresh air or mixture combustible gas to each cylinder, and dischargeswaste gas timely. In addition, it can seal the cylinder when the inlet and exhaust valveare closed. The quality of valve-train can affect the performance, fuel economy andemissions greatly. In addition, if it is unreasonable, valve-train may make noise andvibration which affect the comfort. So in view of the importance of valve-train, it isnecessary to make rational design of the valve-train to match the engine well.Firstly, this paper establishes three-dimensional model of valve-train based onthe Pro/Engineer software for analysis and optimization. Then, the author makes testof the engine to obtain the power performance and fuel economy. Construct the modelof performance simulation based on the GT-Power software and make calibrationaccording to the test data.Secondly, build up the kinematics and dynamics model on valve train of the highspeed gasoline engine by the AVL_EXCITE Timing Drive software. Make analysis ofthe current valve-train refer to the criteria of evaluation. The problems will be found.Through the AVL_EXCITE Timing Drive software, the author redesigns the camprofile and makes analysis to verify whether it meets the engineering requirementabout the kinematics and dynamics. Make accurately simulation by the GT-Powersoftware to check out the performance of the engine modified.Finally, with the help of the Pro/Engineer, Hypermesh, ABAQUS, DesignLife,the author makes structure strength and fatigue analysis of key parts of valve train,such as inlet camshaft.All in all, through the above analysis and optimization calculation, it is provedthat the valve-train can work well under the rated speed and the engine performance isimproved.