论文标题
振荡等离子体推进器的性能
Performance of Oscillating Plasma Thrusters
论文作者
论文摘要
传统表达式和定义描述了等离子体推进器的性能，包括推力，特定的脉冲和推进器效率，假设稳态血浆流动流动速度恒定。但是，对于这些推进器来说，血浆表现出不稳定的行为，导致推力和排气速度的时间变化。例如，在霍尔推进器中，电离不稳定性导致排放电流（所谓的呼吸振荡），血浆密度，离子能以及离子流的强烈振荡。在本文中，我们重新审视推力和推力效率的制定，以说明离子参数的时间变化，包括离子能和离子流之间的相移。对于正弦振荡，发现推力可能会改变超过20％。结果表明，通过调节特定振幅的离子能，可以在此类方案中最大化推力。最后，得出了调制推进器的推进器效率的表达式，以显示此类推进器中效率低下的机制。
Traditional expressions and definitions describing performance of plasma thrusters, including the thrust, specific impulse, and the thruster efficiency, assume a steady state plasma flow with a constant flow velocity. However, it is very common for these thrusters that the plasma exhibits unstable behavior resulting in time-variations of the thrust and the exhaust velocity. For example, in Hall thrusters, the ionization instability leads to strong oscillations of the discharge current (so-called breathing oscillations), plasma density, ion energy, and as a result the ion flow. In this paper, we revisit the formulation of the thrust and the thrust efficiency to account for time variations of the ion parameters including the phase shift between the ion energy and the ion flow. For sinusoidal oscillations it was found thrust can potentially change more than 20%. It is shown that by modulating ion energy at specific amplitudes, thrust can be maximized in such regimes. Finally, an expression for the thruster efficiency of the modulating thruster is derived to show a mechanism for inefficiencies in such thrusters.
