DOI
https://doi.org/10.25772/4HZS-YY96
Defense Date
2021
Document Type
Thesis
Degree Name
Master of Science
Department
Mechanical and Nuclear Engineering
First Advisor
Gennady Miloshevsky
Abstract
Warm dense plasma is the matter that exists, roughly, in the range of 10,000 to 10,000,000 Kelvin and has solid-like densities, typically between 0.1 and 10 grams per centimeter. Warm dense fluids like hydrogen, helium, and carbon are believed to make up the interiors of many planets, white dwarfs, and other stars in our universe. The existence of warm dense matter (WDM) on Earth, however, is very rare, as it can only be created with high-energy sources like a nuclear explosion. In such an event, theoretical and computational models that accurately predict the response of certain materials are thus very important. Unfortunately, given both the impracticality of producing WDM on Earth and the inherent complexity of the matter itself (partial ionization, non-negligible electron-nuclei interactions, etc.), modeling WDM has proved strenuous and problematic. Despite this difficulty and complexity, advances in Density Functional Theory Molecular Dynamics (DFT-MD) have made such simulations possible. In this thesis, elemental carbon was modeled because of its low atomic number and its relative abundance of experimental data. The Car-Parrinello MD package implemented in the code Quantum ESPRESSO was used to simulate warm dense carbon. Carbon cells were comprised of 24 atoms assigned random positions and were modeled at densities typical of WDM. System temperature was set with the Nosé-Hoover thermostat and by rescaling ionic velocities, and each cell was run at temperatures up to 10,000 Kelvin. Simulation results were plotted, analyzed, and compared to those presented in the literature. Overall, results show pressure divergence that differs substantially with current DFT models of warm dense carbon. This work continues the application of MD simulations to WDM and provides a basis for future research into thermodynamic properties of warm dense plasmas.
Rights
© The Author
Is Part Of
VCU University Archives
Is Part Of
VCU Theses and Dissertations
Date of Submission
5-11-2021
Included in
Atomic, Molecular and Optical Physics Commons, Computer Sciences Commons, Condensed Matter Physics Commons, Materials Science and Engineering Commons, Mechanical Engineering Commons, Nuclear Commons, Nuclear Engineering Commons, Plasma and Beam Physics Commons, Quantum Physics Commons