Modeling of an inductively coupled plasma at reduced pressures
Modeling of an inductively coupled plasma at reduced pressures
复制标题
减压下电感耦合等离子体的建模
DOI：
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
E. Pfender
中科院分区：
文献类型：
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作者：
S. Paik;E. Pfender
在该实验室中，在降低的压力下的等离子体烧结实验揭示了由于表面上的解离和/或电离物质的重组而对陶瓷样品的有效加热。为了建立这种等离子体烧结过程的模型，有必要首先考虑等离子体本身。因此，一个合适的模型，RF电感耦合等离子体已被开发考虑降低的压力。当压强降低时，电子密度也会在固定的电子温度下降低，导致化学平衡的实质性偏离。由于在减压下电子和重粒子之间的碰撞耦合很差，因此也必须预期与动力学平衡的大偏差。该模型是基于一个旋转对称的等离子体包含在石英管。功率水平范围为1.5至3 kW，操作压力范围为1至0.01 atm。该模型包括了化学平衡和动力学平衡的偏离。两个温度的等离子体的热力学和输运性质用于此建模工作。结果表明，对于低于0.1大气压的压力，有一个强大的双极通量的电荷载流子的限制壁，导致显着的变化，整个管的温度。电子温度随着压力的降低而迅速升高，而重粒子温度则降低。
Plasma sintering experiments in this laboratory at reduced pressures revealed efficient heating of the ceramic sample due to recombination of dissociated and/or ionized species on the surface. For establishing a model for this plasma sintering process, it is necessary to first consider the plasma itself. Therefore, a suitable model for an RF inductively coupled plasma has been developed considering reduced pressures. As the pressure decreases, the electron density also decreases at a fixed electron temperature, causing substantial deviations from chemical equilibrium. Due to the poor collisional coupling between electrons and heavy particles at reduced pressures, large deviations from kinetic equilibrium have also to be expected. The model is based on a rotationally symmetric plasma contained in a quartz tube. The power level ranges from 1.5 to 3 kW and the operating pressure is varied from 1 to 0.01 atm. Both deviations from chemical and kinetic equilibrium are included in this model. Thermodynamic and transport properties for two-temperature plasmas are used for this modeling work. The results indicate that for pressures below 0.1 atm, there is a strong ambipolar flux of charge carriers to the confining walls, leading to significant variations of the temperature across the tube. The electron temperature increases rapidly as the pressure decreases, whereas the heavy-particle temperature decreases.