A multispecies, multifluid model for laser–induced counterstreaming plasma simulations. (30th May 2019)

• Record Type: Journal Article
• Authors: Ghosh, D.; Chapman, T.D.; Berger, R.L.; Dimits, A.; Banks, J.W.
• Is Part Of: Computers & fluids. Volume 186(2019)
• Page Start: 38
• Page End: 57
• Publication Date: 2019-05-30
• Subjects: Plasma interpenetration -- Multifluid plasma -- Conservative finite-difference method -- Laser–induced plasmas; 76X05 -- 35L04 -- 35L65 -- 65M06; Fluid dynamics -- Data processing -- Periodicals; 532.050285
• DOI: 10.1016/j.compfluid.2019.04.012
• Languages: English
• ISSNs: 0045-7930

Abstract

Highlights: Plasma interpenetration is an important phenomenon in several applications. Single-fluid codes are not able to model this, and we need a multifluid approach. We implement a conservative, finite-difference multifluid code for this application. Problems representative of laser-induced plasma experiments are simulated. Abstract: The interpenetration of counterstreaming plasmas is an important phenomenon in several application areas, such as astrophysical flows, design of controlled fusion devices, and laser–induced plasma experiments. Multispecies "single-fluid" codes are unable to model this phenomenon due to the single velocity representation for all the species/fluids. Kinetic codes, though capable of modeling interpenetration, are computationally prohibitive for at-scale simulations. In this paper, we propose a multifluid model that solves the fluid equations for each ion fluid or stream. This allows distinct flows that interact with each other through electrostatic and collisional forces. We introduce and describe our code, EUCLID, that uses a conservative finite-difference formulation to discretize the governing equations in space. The 5th-order Monotonicity-Preserving WENO scheme is used for the upwind approximation of the hyperbolic flux, and the explicit 4th-order Runge–Kutta scheme is used for time integration. The code is verified for several benchmark cases and manufactured solutions. We simulate one- and two-dimensional interactions of counterstreaming plasmas in vacuum as well as in the presence of gas fill, where the setups are representative of laser-induced plasma experiments.