Date of Award
Spring 5-2017
Access Type
Thesis - Open Access
Degree Name
Master of Science in Aerospace Engineering
Department
Aerospace Engineering
Committee Chair
Eric Perrell
First Committee Member
L.L. Narayanaswami
Second Committee Member
William Engblom
Abstract
With renewed interest in planetary atmospheric entry, descent, and landing, NASA has noted a need for improved physics modeling in computational fluid dynamics. Uncertainty in experimental data used in radiation heat transfer computations leads to “over-engineering” of entry body heat shields, at large weight and cost penalties. There is interest in developing hypersonic thermophysics models from the known “first principles” of physics.
A method for computing high temperature gas emissivity and absorptivity from quantum mechanics principles is developed. The Schroedinger wave equation is cast as a discretized matrix eigenvalue problem which is solved using the ERAU parallel supercomputer. The numerical solutions for the wave functions are then integrated to determine the Einstein coefficients for emission and absorption, and hence the gas properties are tabulated as functions of temperature and pressure.
All of the published works found thus far assume Dirichlet or von Neumann boundary conditions for the eigenvalue problem. At best this presumes a priori knowledge of the solution. In general, it is incorrect. The novel boundary condition treatment used here admits simultaneous solution for several wave functions, unlike the “shooting methods” in most textbooks. Therefore the novel boundary condition treatment is used in this thesis. The hydrogen atom is studied, as analytical solutions for verification exist. Numerical solutions have been completed and compare very well with analytical solutions, and with experimental data maintained by National Institutes of Standards (NIST).
Scholarly Commons Citation
Thomas, Fanny, "Ab Initio Computation of Radiative Properties of Monatomic Hydrogen" (2017). Doctoral Dissertations and Master's Theses. 344.
https://commons.erau.edu/edt/344