An Implicit Fluid-Particle Model for Ion Beam-Plasma Interactions

A new method for modeling the hydrodynamic behavior of collisional plasmas is presented. The numerical model uses finite-sized “particles” in a full particle-in-cell (PIC) representation of the plasma, where full is used to emphasize that a complete characterization of the plasma is obtained solely with the properties carried by the particles. Plasma motion is modeled by integrating the equations of motion for each particle implicitly in time on an arbitrarily-adaptive computational grid. The full PIC method is a conservative scheme that has no numerical diffusion and is ideally suited for modeling distorted and unstable hydrodynamic fluid flow. Computational results of a shock tube problem, the Rayleigh-Taylor (R-T) instability, and planar heavy-ion-driven ICF target implosions illustrate the properties of the method.