A one dimensional model using chemical kinetics theory and empirical electron impact collision cross sections is used to calculate the composition of molecular propellant in a cylindrically symmetric electrodeless thruster with a magnetic nozzle. When applied to water vapor, plasma composition along the thruster length changes from regimes dominated by molecular ions and neutral fragments to that dominated by atomic ions. The impact of dissociation losses on performance indicates there is a peak in efficiency at an optimum pressure times thruster length, p 0 L *, between 0.03 and 0.3 mTorr m, requiring electron temperature T e > 15 eV. Operation near this peak requires a power per mass flow rate ##IMG## [http://ej.iop.org/images/0963-0252/29/4/045007/psstab759eieqn1.gif] {$P/\dot{m}\gt 0.8$} kW mg −1 s −1 , which limits frozen flow losses to 20%–30% and enables specific impulses betwee...

中文翻译：

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水蒸气推进剂用于无电极等离子体推进的比例定律

使用化学动力学理论和经验电子碰撞碰撞截面的一维模型来计算具有电磁喷嘴的圆柱对称无电极推进器中分子推进剂的组成。当应用于水蒸气时，沿推进器长度方向的等离子体组成会从以分子离子和中性碎片为主的状态变为以原子离子为主的状态。离解损失对性能的影响表明，在最佳压力乘以推进器长度p 0 L *时，效率在0.03至0.3 mTorr m之间存在一个峰值，需要电子温度T e> 15 eV。在此峰值附近运行需要每质量流量的功率## IMG ## [http://ej.iop.org/images/0963-0252/29/4/045007/psstab759eieqn1.gif] {$ P / \ dot { m} \ gt 0.8 $} kW mg -1 s -1，