Simulation Of Low Temperature Premixed Charge Combustion On VM R425DOHC Diesel Engine

This paper makes a deep research on Exhaust gas recirculation (EGR) characteristic, EGR control strategy and diesel engine low temperature premixed combustion (HCCI). The paper builds a simulation model of VM R425DOHC using GT-POWER software. The simulation results show that this model can simulate the diesel engine. EGR is investigated using the model. The results show that the start of ignition will delay and the peak pressure will drop with the growing of the EGR rate. The start of ignition will bring forward and the peak heat release rate will descend with the growing of the EGR temperature. Base on the simulation study this paper brings forth the linear computational method for the inlet mass flow based the temperature correction and the EGR closed-loop control strategy for the first time. It helps to realize the diesel engine HCCI that EGR can be precisely controlled; the injection strategy research is carried out by experiments. The results show that early injection, late injection and narrow spray angle injector can effectively be used in the low temperature premixed combustion. The early injection need control the detonation and NOX emissions. The late injection need control the Soot emissions when the engine load spreads. The narrow angle injector can give a wide angle injection without spray impinging on the cylinder wall. This injection strategy has certain reference significance.