Study of variable nozzle turbocharger matching on the natural gas engine

A variable nozzle turbocharger(VNT) was applied on the 488 natural gas engine, the VNT electronically controlled system was designed, and the VNT matching regulation was studied based on the engine tests. The experimental results show that the VNT regulating discipline for the CNG engine is related to the throttle valve opening and the engine revolution speed. The power and torgue of the CNG engine increase remarkably by using VNT, the maximum power rises from 58 kW to 73 kW, the maximum torque increases from 156 N · m to 212 N · m, and the revolution speed at the maximum torque decreases, the economy and power performance of the CNG engine are improved greatly.