环形等离子体激励器的温升效应

摘要

等离子体强化燃烧的机理主要表现为3种效应:热效应、化学效应和气动效应.基于等离子体气体放电的基本理论,结合工程实际需要,设计了一种环形等离子体激励器.在冷态条件下,研究了环形等离子体激励器的温升效应.重点分析了距离、空气流量、脉冲频率、占空比和氩气流量对温升的影响.结果表明,等离子体放电能够产生有效的温升,但是与燃烧产生的温升相比相对较小;距离等离子体激励器越远温升越小;空气流量增大,温升越小;放电频率在600 Hz左右时,温升效果较好;占空比越大,温升量更高,温升速度更快;加入一定量的氩气能够提升放电强度,温升量有所增加.与气流静止的放电相比,气流流动时,放电均匀性有较为明显的提升.%The mechanism of plasma assisted combustion contains three effects:thermal effect,chemical effect and aerodynamic effect.Based on the theory of plasma gas discharge,combined with the actual needs of engineering,the toroidal plasma igniter was designed.The temperature rising effect of the toroidal plasma igniter was studied without combustion.The influence of distance,air flow,pulse frequency,duty cycle and argon flow on temperature rising was analyzed.The results show that plasma discharge can cause an effective temperature rising,but compared with that of combustion,the temperature rising of plasma discharge is lower.The farther the distance from the plasma igniter,the lower temperature rising.The temperature rising is lower when air flow increases.The temperature rising effect is better at 600 Hz discharge frequency.The larger the duty cycle,the more and faster the temperature rise.The addition of a certain amount of argon can enhance the discharge intensity,and the temperature rise is increased.Compared with the stationary conditions,the discharge becomes more uniform under the flow conditions.