Norman G E, Timofeev A V
Joint Institute for High Temperatures of RAS, Moscow, Russia.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Nov;84(5 Pt 2):056401. doi: 10.1103/PhysRevE.84.056401. Epub 2011 Nov 1.
A system of equations describing motion of dust particles in gas discharge plasma is formulated. This system is developed for a monolayer of dust particles with an account of dust particle charge fluctuations and features of the discharge near-electrode layer. Molecular dynamics simulation of the dust particles system is performed. A mechanism of dust particle average kinetic energy increase is suggested on the basis of theoretical analysis of the simulation results. It is shown that heating of dust particles' vertical motion is initiated by forced oscillations caused by the dust particles' charge fluctuations. The process of energy transfer from vertical to horizontal motion is based on the phenomenon of the parametric resonance. The combination of parametric and forced resonances explains the abnormally high values of the dust particles' kinetic energy. Estimates of frequency, amplitude, and kinetic energy of dust particles are close to the experimental values.
建立了一个描述气体放电等离子体中尘埃粒子运动的方程组。该方程组是针对单层尘埃粒子建立的，考虑了尘埃粒子电荷波动以及放电近电极层的特性。对尘埃粒子系统进行了分子动力学模拟。基于对模拟结果的理论分析，提出了尘埃粒子平均动能增加的机制。结果表明，尘埃粒子垂直运动的加热是由尘埃粒子电荷波动引起的强迫振荡引发的。从垂直运动到水平运动的能量转移过程基于参量共振现象。参量共振和强迫共振的结合解释了尘埃粒子动能异常高的值。对尘埃粒子的频率、振幅和动能的估计与实验值接近。
