Study on Varying Altitude Self-Adaptive Turbocharging System for Diesel Engine

On the basis of variable nozzle turbocharging a varying altitude self-adaptive turbocharging system for diesel engine was established.The comparative experiments were performed on the simulation test-bed to simulate the conditions of varying altitude of 0～4 000 m,to study effects on engine charge exchanging process and performance.As a result,engine power drop is recovered and the problems of engine misfire at low speed and turbocharger surge at high altitude are solved.The speed of max.torque point at 4 000 m altitude returns to 1 300 r/min,the same as on plain,and the torque drop is less than 5 %,meeting expected objective.It can be concluded that the variable nozzle turbocharging has a certain potentialities for diesel engine power recovery at high altitude and heat load reduction.