Study on variable geometry exhaust manifold turbocharging system for six-cylinder diesel engine

摘要

The variable geometry exhaust manifold (VGEM) turbocharging system can realise the switch between two charging modes by controllable valves, and it can perform well both at high and low speed operations. In order to apply the VGEM turbocharging system to a six-cylinder diesel engine, this paper puts forward a newly designed VGEM turbocharging system. In this paper, first, the simulation of the VGEM turbocharging system has been carried out by GT-POWER. The simulation results indicate that the brake specific fuel consumption (BSFC) can be reduced by 5-4 g kWh~(-1) on the rated operation condition. Then, the simulated experiments of the VGEM turbocharging system have been performed. Two charging modes of the VGEM turbocharging system have been simulated by changing the exhaust manifold structure, from the original exhaust manifold to the newly designed exhaust manifold. The experimental results indicate that the BSFC of the VGEM turbocharging systems can be reduced by 4-7 g kWh~(-1) on the rated operation condition. A detailed analysis on the experiment results has been presented.