Effect of intake timing on engine dynamic performance based on AVL BOOST
                                            ZHANG Chao shan1, XIONG Shu sheng2, SONG Hong jian2, ZHENG Yi kun2
(1.School of Mechanical and Electrical Engineering, Hangzhou Polytechnic, Hangzhou 310014, China;2.College of Energy Engineering, Zhejiang University, Hangzhou 310027, China）

Abstract: Aiming at the intake valve timing having a great effect on the volumetric efficiency of the engine, simulation model of 486 gasoline engine was built up by using AVL BOSST software. The simulation model of the intake performance of the gasoline engine was established and verified. The influence of the parameters such as speed and variable timing on the engine performance was studied. The results show that the different intake valve opening time mainlyinfluents the effect of the gas fluctuation: delaying the intake valve opening time can make full use of the intake inertia supercharging effect toincrease the torque at high speed; the intake valve should be opened in advance to ensure the maximum effective compression ratio at low speed, when the resonant intake effect disappeared. The variable intake timing mechanism is installed on the engine to optimize the intake timing at each speed, which has a great effect on the improvement of the dynamic performance of the low speed and part of the high speed zone.

Key words: gasoline engine; intake valvetiming; volumetric efficiency;inertia supercharging; power performance