摘要
消融放电毛细管等离子体发生器产生的等离子体射流具有高密和相对低温的特性,在许多科学研究和工业应用领域都具有潜在的应用前景。为此,利用数值模拟的方法考察了在1 kJ放电能量水平下两间隙毛细管的长度和半径、主放电电容器组的电容和起始充电电压等放电参数对毛细管出口参数的影响。研究表明,各放电参数的改变都能引起出口处的质量密度、压强的大幅度改变,而出口温度和出口速度相对保持稳定。其中,主放电电容器组充电电压、电容值增大、毛细管半径变小时,所有的出口参数都相应增大;而毛细管长度增大时,密度和压强随之增大,温度和速度反而减小。
Ablative capillary discharge plasma jets are characterized by high density and relatively low temperature. The devices of this kind of plasma jets are of importance to a variety of applications. Two-gap capillary plasma generator （TGCPG） is a realistic alternative to the conventional capillary in electrothermal launchers and a versatile capillary plasma generator for other applications. It is designed to accomplish two goals： repetitive operation and a compact power supply system in which capillary itself serves as a closing switch, thus the conventional closing switches in the power supply system can be eliminated. The TGCPG is composed of two gaps and three electrodes, differing from the conventional capillary in which it contains a trigger circuit and a trigger electrode （TE）. When the triggering high-voltage pulse is applied, the first gap between the cathode and the TE is broken down, and a small energy stored in trigger circuit is dissipated into this gap, then a plasma jet is formed, which can flow into the second gap between the anode and the TE to ignite the main discharges between the anode and the cathode. The exit parameters of TGCPG including mass density, pressure, temperature and velocity are of vital for application purposes, from which the properties of the plasma jets can be calculated. In this paper, theoretical calculations of the main discharges of TGCPG are performed with a one-dimensional （1-D）, time-dependent plasma model. Some numerical results about the influence of capillary size, capacitance of the main discharge capacitor bank and its initial charged voltage to the exit parameters of TGCPG are obtained. It is found that the mass density and pressure can be drastically changed while the temperature and velocity of the plasma jets are relatively stable. Both an increase of capacitance or voltage and a decrease of capillary radius will lead to an increase of all exit parameters; on the other hand, an increase of capillary length will leads to an increase of the mass density and pressure, but a decrease of temperature and velocity.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2006年第6期72-74,112,共4页
High Voltage Engineering
关键词
消融放电
等离子体发生器
等离子体射流
数值模拟
出口参数
ablative capillary discharge
plasma generator
plasma jet
numerical calculation
exit parameter
