Interpenetration and kinetic mix in weakly collisional, fully-ionized plasma jets
Abstract/Contents
- Abstract
- Laser-driven "inverted corona" fusion targets have attracted interest as a low-convergence neutron source and as a platform for studying kinetic physics in inertially confined plasmas. These targets consist of a fuel layer lined along the interior surface of a hollow or gas-filled plastic hohlraum. The plasma streams generated in vacuum targets are initially nearly collisionless as they converge, leading to wide interaction length scales and long interaction time scales as the jets interpenetrate. With the inclusion of a low-density gas fill, ejected particles from the shell can pass far into the gas before colliding, leading to significant mixing across the gas-shell interface. Such interactions are difficult to accurately model using standard hydrodynamic simulations, which assume high collisionality. In this work we model the system using a kinetic-ion, fluid-electron hybrid particle-in-cell (PIC) approach. We also demonstrate the potential of the hybrid-PIC approach for full-scale modeling and experimental design. The entire system is modeled in one integrated simulation, including laser energy deposition, hydrodynamic/kinetic evolution of the plasma, and fusion dynamics. Simulations demonstrate significant kinetic effects (interpenetration, beam-beam fusion, and weakly collisional electrostatic shocks) that are mediated by collisional processes and can be tuned by changing the initial fill pressure of the gas. These effects are detectable through neutron diagnostics. Using two-dimensional simulations we also investigate compression symmetry, hotspot velocity, and directional differences in neutron spectra, as well as make comparison with x-ray emission images. Predictions of neutron yield scaling vs. gas pressure show excellent agreement with experimental data recorded at the OMEGA laser facility, suggesting that one-dimensional kinetic mechanisms may be sufficient to capture the mix process.
Description
| Type of resource | text |
|---|---|
| Form | electronic resource; remote; computer; online resource |
| Extent | 1 online resource. |
| Place | California |
| Place | [Stanford, California] |
| Publisher | [Stanford University] |
| Copyright date | 2023; ©2023 |
| Publication date | 2023; 2023 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Author | Riedel, William |
|---|---|
| Degree supervisor | Cappelli, Mark A. (Mark Antony) |
| Thesis advisor | Cappelli, Mark A. (Mark Antony) |
| Thesis advisor | Glenzer, S. H, 1966- |
| Thesis advisor | Meezan, Nathan |
| Degree committee member | Glenzer, S. H, 1966- |
| Degree committee member | Meezan, Nathan |
| Associated with | Stanford University, School of Engineering |
| Associated with | Stanford University, Department of Mechanical Engineering |
Subjects
| Genre | Theses |
|---|---|
| Genre | Text |
Bibliographic information
| Statement of responsibility | William Mathews Riedel. |
|---|---|
| Note | Submitted to the Department of Mechanical Engineering. |
| Thesis | Thesis Ph.D. Stanford University 2023. |
| Location | https://purl.stanford.edu/yy667sx1591 |
Access conditions
- Copyright
- © 2023 by william riedel
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
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