The Influence Of Engine Performance Cause By Gas Exchange Status

The intake system has an important influence on the engine. For the naturallyaspirated engine, the intake manifold and the inlet port as the main part whether theymatch with engine partially or not directly affect its power and economy performanceetc. Therefore, the intake manifold and intake port play an important role on theengine developing process. In this paper, to improve the performance of the engine weinvestigate the good matching of the intake manifold and optim ization of the intakeport based on a naturally aspirated engine.After sufficient research on the related literature at home and abroad based onthis engine, the good matching of the intake manifold and optimization of the intakeport will be the main direction to improving performance of the engine. The formermatching length uses the intake manifold wave effects in order to improve the enginetorque, and the latter modifies the structure in order to reduce the flow resistance.Intake manifold matching using software GT-POWER to simulate. By calculatingdifferent length of it finally chooses a kind of intake manifold which is suitable forproject development of this two-stagy variable. In airway optimization use AVL FIREto calculate, and compare the flow coefficient of the intake port built in CATIA, andthen choose a better scheme than origin to develop. Utilize existing cylinder head tocast mold, and modify the intake port sand core to cast optimized cylinder head tosave costs and shorten the development cycle.In terms of airway performance test, in this paper, it introduces the examinationof the Steady Flow Test Bench, and measures the flow coefficient of cylinder headbefore and after optimization. By comparing the test results, it shows that afteroptimization the flow coefficient is better than origin in the case of high valve life.Finally, test the engine related scheme on engine test bench. Select suitablelength of variable intake manifold scheme for different engine speed. The engineperformance is very good compared with the original engine when the variable intakemanifold and optimized inlet port are simultaneously applied.This paper uses the software simulation method to investigate the intakemanifold and intake port, and the simulation results is verified through experimentalmethod. It provides a method for the engine development in this process.