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Abstract We present results and analysis of finite‐difference time‐domain (FDTD) simulations of electromagnetic waves scattering off meteor head plasma using an analytical model and a simulation‐derived model of the head plasma distribution. The analytical model was developed by (Dimant & Oppenheim, 2017b,https://doi.org/10.1002/2017JA023963) and the simulation‐derived model is based on particle‐in‐cell (PIC) simulations presented in (Sugar et al., 2019,https://doi.org/10.1029/2018JA026434). Both of these head plasma distribution models show the meteor head plasma is significantly different than the spherically symmetric distributions used in previous studies of meteor head plasma. We use the FDTD simulation results to fit a power law model that relates the meteoroid ablation rate to the head echo radar cross section (RCS), and show that the RCS of plasma distributions derived from the Dimant‐Oppenheim analytical model and the PIC simulations agree to within 4 dBsm. The power law model yields more accurate meteoroid mass estimates than previous methods based on spherically symmetric plasma distributions.
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Numerical Simulation of Plasma Interfaces Using the Starfish Plasma Simulation Code
A particular challenge for low temperature plasma (LTP) research is the diversity of parameter space and conditions. For plasma systems where the densities are not low, the kinetic theory is time-consuming and becomes unrealistic. In this regime, the particle-in-Cell (PIC) method is appropriate where the evolution of a particle system at every time step consists of an Eulerian stage and a Lagrangian stage. The PIC method can deal with complex geometries and large distortions in the field. The PIC solver, Starfish, is a two-dimensional plasma and gas simulation code operating on structured 2D/axisymmetric Cartesian or body fitted stretched meshes. The purpose of this study is to use the Starfish Plasma Simulation Code for numerical simulations of plasma interfaces. Specifically, two applications are considered: 1) the modeling of a large area (30 cm x 30 cm) microwave plasma chemical vapor deposition system, and 2) the understanding of LTP treatment on surface modification of polycaprolactone pellets and thermal properties of extruded filaments. With the exact geometries and experimental results being provided, numerical simulations of these two applications are ongoing.
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- Award ID(s):
- 1655280
- PAR ID:
- 10221582
- Date Published:
- Journal Name:
- AiAA Aviation Forum 2020
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.2514/6.2020-3245
