Nonlinear Theory Of Dust Void Formation In Dust Plasma

Dusty plasma exists widely in space plasma, laboratory plasma and high-temperature nuclear fusion plasma. Dust voids were found both in experiments and applications. To understand the mechanism of dusty void formation in dust plasma, people used various methods to do their research, gave many different explanations.In 1999, Samsonv and Goree had their experimental study in the first time for ionization instabilities in dust plasma. Their research shows that the ionization instability in dust plasma has two stages--linear stage and nonlinear stage. In linear stage, all harmonic waves are excited; the instability mode is filament mode. In nonlinear stage, all harmonic waves fall into zero frequency, the instability mode is 'great void mode'. They observed a formation and an evolution of dust void in their experiment, and used various experimental methods in their research work.In 2001, Xiaogang Wang et al. analyzed theoretically in detail about ionization instabilities and resonance acoustic modes in dust plasma. They gave the dispersion relations and established the theory of ionization instability in dust plasma in linear stage.In 2003, Avinash et al. in the first time established a nonlinear theory of dust void formation in dusty plasma in one-dimensional Cartesian coordinate system. Their research shows that, in the dust void formation and evolution process, the dust particles are mainly affected by electrical field force and ion drag force. In their research work, effect of dust convection was not considered.In this paper, in one-dimensional cylindrical coordinate system, considering effect of dust convection, a mathematical model of dust void formation in dusty plasma is established. The model is solved numerieally. The numerical results of dust void formation and evolution in dust plasma are obtained. The numerical results show that cylindrical coordinate system is more close to the situation about the experiment, and the dust convection has a significant effect for the dust void formation.