Analysis of the Velocity Transient Response of VNT in Turbocharged Diesel & Vehicle

This paper is based on the experiment of variable nozzle turbocharger(VNT) of turbocharged diesel vehicle in plateau and plain under different operating states,which are starting,accelerating and slowdown.And made the test research on the transient speed of VNT and diesel engine and the velocity of vehicle in plain and plateau.These parameters have been compared and analysed.The result of study shows that the speed of VNT lags behind in the speed of engine in engine starting operating model,transient response of the speed of VNT varies fast with the speed of the engine in starting and accelerating operating mode,the speed of VNT increases with increasing of the speed of the engine in gear changing and accelerating operating model,VNT speed presents the downward trend when the speed of the engine drops in moderating the operating mode.For VNT effective regulation,the turbine does not overspeed.VNT can improve the transient state characteristic of the turbocharged diesel engine,and benefits the steering performance of the vehicle in different operating mode.