二次喷射对低负荷工况下汽油压燃燃烧影响的数值研究OA

In order to address the stability challenges associated with gasoline compression ignition at lowload conditions,the effects of injection strategy parameters on stratification,heat release rates and NO formation were investigated at low load condition.3D simulations were performed using the ANSYS FORTE software to examine the combustion characteristics of iso-octane spray flames in an engine sector.The results indicate that the combustion in some double injection cases was characterized by rapid and concentrated combustion when the fuel distribution was helpful to making the fully oxidation essentially occur in rich zone.The peak of heat release rate increased from 180 J/(°)in single injection to 300 J/(°)in double injection.When the interval time between two injections was fixed at 4.0°,the integral area under p-V curve increased as the split ratio increased from 10%to 40%.When the split ratio was fixed at 20%,there would be a loss of fuel since pilot fuel was injected too early in the case of 12.0° interval time.Compared to those in single injection,NO formation in double injections increases,and soot formation in double injections decreases because of higher in-cylinder temperatures.