skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Theoretical and numerical modelling of shocks in dusty plasmas

Abstract

The formation of dust acoustic (DA) and dust ion-acoustic (DIA) shocks are are studied theoretically and numerically by means of simple-wave solutions and a comparison between fluid and kinetic model for DIA waves. A fluid model admits sharp discontinuities at the shock front while the kinetic model involves Landau-damping of the the shock front.

Authors:
;  [1]
  1. Institut fuer Theoretische Physik IV, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)
Publication Date:
OSTI Identifier:
20726732
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 799; Journal Issue: 1; Conference: 4. international conference on the physics of dusty plasmas, Orleans (France), 13-17 Jun 2005; Other Information: DOI: 10.1063/1.2134585; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COMPARATIVE EVALUATIONS; DUSTS; FLUIDS; ION ACOUSTIC WAVES; IONS; LANDAU DAMPING; MATHEMATICAL SOLUTIONS; NUMERICAL ANALYSIS; PLASMA; PLASMA SIMULATION; SHOCK WAVES

Citation Formats

Eliasson, B., and Shukla, P.K. Theoretical and numerical modelling of shocks in dusty plasmas. United States: N. p., 2005. Web. doi:10.1063/1.2134585.
Eliasson, B., & Shukla, P.K. Theoretical and numerical modelling of shocks in dusty plasmas. United States. doi:10.1063/1.2134585.
Eliasson, B., and Shukla, P.K. Mon . "Theoretical and numerical modelling of shocks in dusty plasmas". United States. doi:10.1063/1.2134585.
@article{osti_20726732,
title = {Theoretical and numerical modelling of shocks in dusty plasmas},
author = {Eliasson, B. and Shukla, P.K.},
abstractNote = {The formation of dust acoustic (DA) and dust ion-acoustic (DIA) shocks are are studied theoretically and numerically by means of simple-wave solutions and a comparison between fluid and kinetic model for DIA waves. A fluid model admits sharp discontinuities at the shock front while the kinetic model involves Landau-damping of the the shock front.},
doi = {10.1063/1.2134585},
journal = {AIP Conference Proceedings},
number = 1,
volume = 799,
place = {United States},
year = {Mon Oct 31 00:00:00 EST 2005},
month = {Mon Oct 31 00:00:00 EST 2005}
}
  • Theoretical and numerical studies of self-steepening and shock formation of large-amplitude dust ion-acoustic waves in dusty plasmas are presented. A comparison is made between the nondispersive two fluid model, which predicts the formation of large-amplitude compressive and rarefactive dust ion-acoustic shocks, Vlasov simulations, and recent laboratory experiments.
  • The Korteweg-de Vries-Burgers equation for the nonlinear dust drift wave is obtained which admits solutions in the form of solitons, monotonic shocks, and oscillatory shocks in different limits. The relevance of this investigation to laboratory and space plasmas is pointed out.
  • The formation of dust ion-acoustic shocks in a four-component quantum plasma whose constituents are electrons, both positive and negative ions, and immobile charged dust grains, is studied. The effects of both the dissipation due to kinematic viscosity and the dispersion caused by the charge separation as well as the quantum tunneling associated with the Bohm potential are taken into account. The propagation of small but finite amplitude dust ion-acoustic waves is governed by the Korteweg-de Vries-Burger equation, which exhibits both oscillatory and monotonic shocks depending not only on the viscosity parameters {eta}{sub {+-}}={mu}{sub {+-}}{omega}{sub p-}/c{sub s}{sup 2} (where {mu}{sub {+-}}more » are the coefficients of kinematic viscosity, {omega}{sub p-} is the plasma frequency for negative ions, and c{sub s} is the ion-sound speed), but also on the quantum parameter H (the ratio of the electron plasmon to the electron Fermi energy) and the positive to negative ion density ratio {beta}. Large amplitude stationary shocks are recovered for a Mach number (M) exceeding its critical value (M{sub c}). Unlike the small amplitude shocks, quite a smaller value of {eta}{sub +}, {eta}{sub -}, H and {beta} may lead to the large amplitude monotonic shock structures. The results could be of importance in astrophysical and laser produced plasmas.« less
  • Processing plasmas often produce clusters, ranging in size from a few nanometer up to micrometers. Due to their negative charge, clusters are confined by the sheath electric fields until their mass enables gravity to pull them out of the discharge. Examples are discharges in SiH4 or C2H2. Although there is agreement on the global aspects of the chemistry, details on many processes are lacking. This concerns attachment of electrons to large molecules, restructuring leading to a reduction of the hydrogen content, and the interaction between large negative ions and (excited) molecules, radicals, and positive ions of the parent gas. Resultsmore » from a one-dimensional model for a radio-frequency discharge in SiH4/H2 will be used to illustrate the consequences of various assumptions regarding these basic steps in the chemistry.For discharges in mixtures containing hydrocarbons the incorporation of C2 groups in polycyclic aromatic hydrocarbons has been proposed as an additional mechanism for dust formation. This is the main process adopted in astrophysics. Also in Tokamaks the formation of carbonaceous dust is observed, caused mostly by the erosion of carbon containing divertor tiles and redeposited layers on plasma facing components. In case of detached operation the plasma in the divertor will be similar to that of a processing discharge, favoring homogeneous processes. In ITER this will be accompanied by hydrogen ion fluxes up to 1024 m-2s-1 and power fluxes up to 10 MWm-2, leading to evaporation of wall material. Here we will discuss the chemistry in these situations (processing discharges and divertors), indicating open questions regarding cluster formation.« less