空气等离子体点火器的旋流器斜切角对点火器特性的影响

为了优化空气等离子体点火器的几何结构,提高点火器的工作性能,进行了旋流器斜切角(0°、15°、30°和45°)对点火器放电特性、光谱特性、射流特性和点火特性影响的实验研究,获得了点火器特性的变化规律。实验结果表明:在电弧击穿过程中,增大旋流器的斜切角可以降低电弧击穿电压,降低电信号的振荡幅值,缩短击穿时间;在维持电弧过程中,增大旋流器的斜切角可以降低电弧分流的强度,减小阳极烧蚀速率;等离子体点火射流的电子温度和转动温度随旋流器斜切角的增大而先升高后降低,射流的振动温度随旋流器斜切角的增大先降低后升高;减小旋流器的斜切角,可以提高射流抵抗外界气流扰动的能力,增强点火射流的穿透能力;煤油/空气混合气的点火延迟时间随旋流器斜切角的增大先减小后增大;与其他旋流器的斜切角相比,当旋流器斜切角为30°时,点火器射流温度最高,煤油/空气混合气的点火延迟时间最短。

Effect of Swirler Chamfer Angle in Air Plasma Igniter on Characteristics of Igniter

In order to optimize the geometric construction of air plasma igniter and improve the working performance of igniter,we investigated the discharge characteristic,spectral characteristic,jet characteristic and ignition characteristic of igniter,varying with swirler chamfer angles(0°,15°,30°and 45°).The experimental results show that breakdown voltage,amplitude of electrical signal and breakdown time decrease with the increase of swirler chamfer angle during the arc breakdown process.During the arc maintenance process,the level of arc shunt and the anode erosion rate will decrease with the increase of swirler chamfer angle.The electron temperature and rotation temperature of plasma jet increase firstly and then decrease with the increase of the swirler chamfer angle,while the vibration temperature of plasma jet decreases firstly and then increases when the swirler chamfer angle increases.The ability of antagonizing exogenous flow disturbances improves when the swirler chamfer angle decreasing,and the penetration capacity of igniter jet will be improved.The ignition delay time of kerosene-air mixture decreases firstly and then increases with the increase of the swirler chamfer angle.The igniter jet temperature will be the highest,and the ignition delay of kerosene-air mixture will be the shortest when the swirler chamfer angle is 30°,compared with other swirler chamfer angles.