进口参数对等离子体点火过程影响的数值模拟

Numerical Simulation of Inlet Parameters Influence on Plasma Ignition Process

为了研究进口参数对等离子体点火过程的影响规律,建立了燃烧室等离子体点火的数值计算模型,对燃烧室内等离子体点火时的化学反应和流场进行了数值模拟。进而分析了等离子体点火器喷出的射流速度、射流温度和混合气的进口速度等进口参数的变化对燃烧室等离子体点火过程的影响规律。结果表明:在等离子体点火器喷出的高温射流进入燃烧室后,燃烧区域向上游的扩展程度远大于向下游的扩展程度,首先在上游形成稳定燃烧;等离子体射流速度对点火延迟时间的影响相对较小,但可以增强等离子体射流的穿透能力;混合气的点火延迟时间随射流温度的升高而减小,随混合气进口速度的增大而增长。

To investigate the influence of inlet parameters on plasma ignition processes, the chemical reaction of plasma ignition and the change in flow field were numerically simulated after establishing a numerical calculation model of the plasma ignition combustion. Then the influence of jet velocity, jet temperature and mixed gas＇s inlet velocity on the plasma ignition process was analyzed. The calculation results show that, when high temperature plasma jet gets into the combustion chamber, the combustion region extended to the upstream is much larger than that to the downstream, and stable combustion forms in the upstream firstly. The effect of plasma jet velocity on ignition delay time is relatively small, but the increase of jet velocity can enforce the plasma jet＇s penetration ability. The mixed gas＇s ignition delay time increases with decreasing jet temperature and increasing inlet velocity of the mixed gas.