Simulation of High-Energy-Density Plasmas Using a Novel, Fully-Implicit, Particle-in-Cell/Monte-Carlo Algorithm

Project Overview

The goal of this project was to assess the feasibility of simulating high-energy-density (HED) plasmas using a new, fully implicit particle-in-cell/Monte-Carlo collision (PIC-MCC) algorithm that is exactly energy conserving. The motivation for this project is that conventional PIC-MCC algorithms, such as those currently employed in the codes used at LLNL, suffer from a severe failure to conserve energy when considering conditions relevant to many HED plasma physics problems, and thus cannot be efficiently used to study such systems. During this FS LDRD, we developed a prototype code using a new fully implicit method and showed that it can accurately model an important class of HED physics problems with greatly reduced computational resources relative to conventional PIC-MCC codes. This work also resulted in a fundamental understanding of why other methods fail to conserve energy for HED plasma simulations. This was the topic of a paper published in the Journal of Computational Physics.

Mission Impact

HED science and high-performing computing (HPC), simulation, and data science are key core-competency areas enabling LLNL to continue to meet its stockpile-stewardship mission and for progressing basic scientific understanding needed to advance fusion-energy sciences. This project supports both areas by developing a new high-fidelity, kinetic simulation capability and demonstrating that it can be efficiently used to do first-principles studies of the HED plasmas found in both inertial confinement fusion (ICF) and dense Z-pinch (DZP) experiments. Furthermore, ICF and DZP experiments are essential to fusion-energy research and play a central role in the national HED science program.

Publications, Presentations, and Patents

Angus, J. et al. 2022. "On Numerical Energy Conservation for an Implicit Particle-in-Cell Method Coupled with a Binary Monte-Carlo Algorithm for Coulomb Collisions." Journal of Computational Physics 456, 111030 (2022); doi: 10.1016/j.jcp.2022.111030.

Angus, J. "On Numerical Energy Conservation for an Implicit Particle-in-Cell Method Coupled with a Binary Monte-Carlo Algorithm for Coulomb Collisions." Talk, Consortium for Advanced Modeling of Particle Accelerators (CAMPA) Collaboration Meeting, Virtual (Berkeley Lab), 2021.

Angus, J. "On Numerical Energy Conservation for an Implicit Particle-in-Cell Method Coupled with a Binary Monte-Carlo Algorithm for Coulomb Collisions." Talk, International Conference on Plasma Science., Seattle, WA, May 2022.

Angus, J. "On Numerical Energy Conservation for an Implicit Particle-in-Cell Method Coupled with a Binary Monte-Carlo Algorithm for Coulomb Collisions." Talk, Engineering Electromagnetic Section Lighting Talks, Virtual (LLNL), 2022. LLNL-ABS-840209.