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Dawei GUO 《等离子体科学和技术》2018,20(12):125506
A gas injector was designed for the 400 J/pulse prototype of the planar inductive pulsed plasma thruster (IPPT) developed by the National University of Defense Technology (NUDT_IPPTx). As the gas puff distribution over the coil surface is critical to the NUDT_IPPTx functioning efficiently, a fast ionization gauge was developed to investigate the neutral gas pressure profiles to seek the critical time when the thruster is ignited. The gauge was calibrated for argon by using a capacitance manometer. Time-resolved pressure profiles have been acquired in the condition of the gas puff mass matching with the discharge energy and the drive coil parameters of the NUDT_IPPTx. It is demonstrated that the gas injector can supply a gas puff with a sufficiently steep (dp/dt ≈ 770 kPa s-1 ) leading and trailing edge, and the gas puff can be compressed against the drive coil as expected. The critical ignition moment is considered to appear at some instant between 525 μs and 650μs after the valve trigger. 相似文献
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A one-dimensional radial non-uniform fluid model is employed to study plasma behaviors with special emphasis laid on helicon discharges. The plasma density ne, electron temperature Te, electron azimuthal and radial drift velocities are investigated in terms of the plasma radius rp, magnetic field intensity B0 and gas pressure p0, by assuming radial ambipolar diffusion and negligible ion cyclotron movement. The results show that the magnetic confinement plays an important role in the discharge equilibrium, especially at low pressure, which significantly reduces Te compared with the case of a negligible magnetic field effect, and higher B0 leads to a greater average plasma density. Te shows little variations in the plasma density range of 1011 cm-3- 1013 cm-3 for p0 〈 3.0 mTorr. Comparison of the simulation results with experiments suggests that the model can make reasonable predictions of Te in low pressure helicon discharges. 相似文献
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运用拉格朗日方程,建立了磁悬浮动量轮系统径向平动的精确动力学模型,并以应用广泛的PD控制进行了运动分析。研究表明,两自由度径向磁轴承的径向平动方向存在一定的耦合运动,但藕合对运动妁影响甚微,实际控制中可以采用单自由度运动模型替代。这方面的研究对认识磁悬浮动量轮的运动特性有积极的作用。 相似文献
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电磁轴承结构参数设计研究 总被引:5,自引:2,他引:3
以实际工程应用为背景,针对电磁轴承的结构参数设计,分析了忽略铁磁材料磁阻对磁路计算带来的误差。通过对控制器参数的研究,表明磁轴承最终的控制刚度不仅与控制器有关,而且受结构参数的制约。从提高控制线圈电流和磁力的响应速度出发,给出了工作气隙、磁极面积与控制线圈的设计原则。这些结构参数与控制性能相关性的研究对于提高电磁轴承的总体性能有积极的作用。 相似文献
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微型卫星激光推进发射概念与影响因素研究 总被引:1,自引:0,他引:1
建立了大气吸气模式与火箭模式组合的激光推进运载器(光船)发射微小卫星入轨的系统概念和分析模型,考虑了推进系统性能、大气传输衰减、模式转换高度、激光器功率、大气飞行阻力、发射点高度等因素对发射系统性能的影响,并对光船发射轨迹进行了计算和讨论。 相似文献
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Kuan QIAO 《等离子体科学和技术》2023,25(2):25504-215
The radiofrequency(RF) inductive cathode has great prospects in space missions with long mission cycles, large speed increments, and rapid response requirements as the main electron source and neutralizer in Hall thrusters and ion thrusters. This paper proposes a comprehensive multi-physics RF inductive cathode model in which the RF electromagnetic field, electrostatic field for extracting electrons, flow field, plasma transport and electrochemical reaction process are all accounted for. Each ph... 相似文献
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