| With the rapid development of computer technology, computational simulationtechnology has become more and more accredited and widely used in the designprocess of a project by manufacturers. Currently, the engine numerical simulationtechnology has been widely used at home and abroad. But, the most important thing ishow to apply theoretical knowledge to optimal design of different engines, and themethod used to complete the reasonable matching among engine parts.In this paper, with the research object of GW4G15car gasoline engine producedby Great Wall Motor Company Limited, the method of numerical simulation&experiment is adopted to optimize its performance, and introduce the effectivesimulation&testing scheme moving towards the design goal step by step.First, based on the original machine performance test data, both the engineperformance simulation software BOOST and structure of valve-train simulationsoftware Excite-TD were applied to complete optimal design, and then optimized theengine’s intake structure size, exhaust structure size and valve timing, emphaticallyanalyzed the exhaust pipe pressure fluctuation, charging efficiency and so on. Themain factors that affect the engine’s performance were found out. Based on simulationresults, take costs and replacement into consideration, choose valve train and exhaustmanifold that have a significant impact on its performance to do optimization work,then rapid prototyping technology was used to make the optimal camshaft and exhaustmanifold.Change different sample parts on the original engine, and then verify the engineperformance by adding different parts one by one through experiment till get the bestperformance. It turned out that, simulation results consistent with the test results, theoptimized parts improved the performance of the gasoline engine, finally satisfied theset of goals. Parallel simulation and experimental method were applied to improve GW4G15gasoline engine’s performance in this subject. Using this method could shorten thedevelopment period, reduce development costs, improve the accuracy of thesimulation, and avoid unnecessary repetitive jobs during the optimal process. Themethod has some practical value for engineers to do performance improvement. |
