为了研究等离子体射流点火提升燃烧室内可燃混合气点火性能的机理,利用建立的实验测量系统,实验研究空气等离子体射流点火器的放电特性和射流特性,并与电火花点火器对比研究在航空煤油/空气混合气中的点火过程。实验结果表明,该空气等离子体射流点火器的击穿电压为9.2k V;相同电压下,电弧电流随工作介质流量的增大而减小,随点火驱动电源输出电流的增大而增大;点火器的伏安特性为下降型;等离子体点火射流长度随点火驱动电源输出电流的增大而增长,随工作介质流量的增大,先增长后缩短;来流速度对等离子体点火射流产生较大影响;等离子体射流点火延迟时间小于电火花点火。
In order to investigate the mechanism of improving the combustible mixture ignition performance in combustion chamber with plasma jet igniter,the discharge characteristics and jet characteristics of air plasma jet igniter were explored based on experimental measurement system. The ignition of kerosene/air mixtures in combustion chamber was also conducted,and comparison was made between the air plasma jet igniter and spark iginter. The results show that the breakdown voltage of the ignitor is 9.2k V. With the increasing of medium flow and the current output from driving electrical source,igniter electrode current is gradually decreased and then increased,respectively. The igniter owns a decreasing current-voltage characteristic. With the increasing of medium flow,the length of plasma jet first increased and then decreased,and the length of plasma jet gradually increased along with the increasing of the current output from driving electrical source. The airflow has much effect on the plasma jet. Plasma jet ignition delay time is shorter than that of spark ignition.