基于有限元分析的激波管电晕放电单元设计及特性分析

Design and Characteristic of Corona Discharge Unit in Shock Tube Based on Finite Element Analysis

关键词:  激波管  电晕放电  放电单元  有限元

Key words:  Shock tube  Corona discharge  Discharge unit  Finite element

摘要:

为在激波管中研究等离子体对碳氢燃料点火延迟时间的影响，基于有限元分析方法，模拟了在激波管末端面使用同轴放电的方式对激波管壁进行放电，计算了放电过程中的电参数，相比圆柱形电极，带尖端的放电电极更容易在局部产生更高的电场强度。内径10cm的圆筒中，对于直径1cm的电极，附加100kV的电压周围最大电场强度为176kV/cm。对于顶端带尖端的电极，尖端处的最大电场强度达到了435kV/cm。而对于侧面带尖端的电极，尖端处的最大电场强度约为250kV/cm。依据仿真的结果，设计了激波管放电单元，并进行基于激波管的电晕放电实验。研究了不同内径金属圆筒中电晕放电与电弧放电的电压范围。当圆筒内径为40mm时，适合电晕放电的功率范围为3～16.7W。圆筒内径为100mm时，适合电晕放电的功率范围为1.6～50.5W。

Abstract:

In order to study the effect of ignition delay of hydrocarbon fuel acted by plasma，the discharge at the end of the shock tube in coaxial discharge was simulated based on finite element analysis. The electrical parameters in the discharge process were calculated. The electrode with tips would produce higher electric field intensity locally compared with the cylinder electrode. 100kV voltage applied on 1cm diameter electrode in 10cm inner diameter cylinder would produce 176kV/cm maximum electric field intensity. The electrode with tip at top would produce 435kV/cm maximum electric field intensity and the electrode with tip at side would produce 250kV/cm maximum electric field intensity. The discharge unit of the shock tube was designed based on the simulation results and the corona discharge experiment was carried out. The voltage range of corona discharge and arc discharge in metal cylinder of different diameter was studied. The power range is 3～16.7W for the 40mm inner diameter cylinder and 1.6～50.5W for the 100mm inner diameter cylinder when corona discharge was taking place.