(1.Vehicle Engineering Department,Chongqing University of Technology,Chongqing 400054,China;
2.Key Laboratory of Advanced Manufacture and Technology for Automobile Parts,Ministry of Education,Chongqing University of Technology,Chongqing 400054,China)
Aiming at the problem that the engine high-speed power performance was lower than that of the same displacement engine, a method combining multiobjective optimization and test was used to optimize the engine power performance. The one-dimensional model of engine was established and calibrated, and the DOE method was used to analyze the effects of intake delay angle, intake cam maximum lift, compression ratio and other factors on the external characteristics of engine, and the analysis results were in a good response fit. The working performance of engine under high-speed and high-load conditions was optimized by using the genetic algorithm. The flow characteristics of intake port were analyzed by CFD, and the flow coefficient of intake port was improved by improving the structure of intake port. Finally, the intake port steady flow test bench and the engine test bench were built. The experimental results show that the improved intake port flow coefficient increases by 6.51% at maximum, the engine power improves by 15.59%, the torque output increases by 11.92%, and the fuel consumption reduces by 3.33%.
