水工质微波加热推力器的击穿点火与离解损失估算

Breakdown and dissociation loss evaluation of water fed microwave plasma thruster

对水工质微波等离子推力器(MPT),用微波击穿气体放电产生等离子体的条件,数值估算了其点火的可行性;通过化学动力学计算证明了水工质MPT中离解损失的存在,并初步估算了理解损失的大小。结果表明,在1 kW的输入功率下水工质MPT的点火启动并不特别困难,从点火到稳定工作,能量吸收从场致电离、碰撞电离转变为热电离、碰撞电离和场致电离;水在MPT工作过程中会发生离解,离解损失在各类能量损失中所占的比重较大。

The firing condition in water fed microwave plasma thruster （MPT） under the power of 1 kW was studied by numerical evaluation. The dissociation loss was also discussed. The results indicate that it is not so difficult for firing in water fed MPT. The mechanism of energy absorption has a change from electric field ionization and collision ionization to thermal ionization, collision ionization and electric field ionization. The dissociation loss of water fed MPT was found by solving the chemical kinetics equation. The level of dissociation loss is also evaluated using the calculation results.