Generalizations of a Nonlinear Fluid Model for Void Formation in Dusty Plasmas

TL;DR

This paper extends a nonlinear fluid model for void formation in dusty plasmas from one to higher dimensions, incorporating more complete dynamics and demonstrating the robustness of void formation features.

Contribution

It introduces multi-dimensional extensions of a nonlinear fluid model with enhanced dynamical equations for dusty plasma void formation.

Findings

Void formation features are robust across different ion drag functions.

The extended model captures nonlinear growth and saturation mechanisms.

Multi-dimensional simulations show consistent qualitative behavior.

Abstract

New developments in the theory and numerical simulation of a recently proposed one-dimensional nonlinear time-dependent fluid model [K. Avinash, A. Bhattacharjee, and S. Hu, Phys. Rev. Lett. 90, 075001 (2003)] for void formation in dusty plasmas are presented. The model describes an initial instability caused by the ion drag, rapid nonlinear growth, and a nonlinear saturation mechanism that realizes a quasi-steady state containing a void. The earlier one-dimensional model has been extended to two and three dimensions (the latter, assuming spherical symmetry), using a more complete set of dynamical equations than was used in the earlier one-dimensional formulation. The present set of equations includes an ion continuity equation and a nonlinear ion drag operator. Qualitative features of void formation are shown to be robust with respect to different functional forms of the ion drag operator.