Masters Theses

Abstract

"This document describes a new modeling technique used to compare thermal and kinetic modification of hydrogen and oxygen gas. The thermal model uses an equilibrium thermodynamic analysis to determine the heat required for given mole fractions of molecular and dissociated products. A kinetic model is developed for a mono-energetic electron beam and a Maxwellian energy distribution. The kinetic model uses electron impact cross sections for excitation, dissociation, and ionization tabulated from available source data between 0-1000 eV. Cross sections are used to calculate forward reaction rates, electron penetration depths, and associated product concentrations for excited, dissociated, and ionized species. The preferred method of energy deposition must show faster rates of forward reaction and larger concentrations of products for lower energy requirements. Overall, thermal energy addition shows 50-90% dissociation in either gas but requires large amounts of energy (10⁷-10⁸ kJ/kg). Kinetic modification, for the range of electron energies tested between 0-1000 eV, shows no significant change in the gas composition. Kinetically produced concentrations of excited, dissociated, and ionized molecules have orders of magnitude between 10⁻¹⁷-10⁻¹⁴ mol/cm³ for the Maxwellian distribution and 10⁻¹⁹-10⁻¹⁴ mol/cm³ for the mono-energetic beam. Qualitatively, the Maxwellian distribution provides faster rates of excitation, while the mono-energetic distribution provides faster rates of dissociation and ionization. Kinetic simulations apply less energy than the thermal model (i.e. 1000 eV = 1.602x10⁻¹⁶ J) and are one-dimensional in nature. Future simulations must include higher energies above 1000 eV, their associated cross sections, and Monte Carlo techniques to quantify the expected advantage of kinetic energy addition over thermal energy addition"--Abstract, page iii.

Advisor(s)

Rovey, Joshua L.

Committee Member(s)

Köylü, Ümit Ö. (Ümit Özgür)
Riggins, David W.

Department(s)

Mechanical and Aerospace Engineering

Degree Name

M.S. in Mechanical Engineering

Sponsor(s)

Missouri Space Grant Consortium

Publisher

Missouri University of Science and Technology

Publication Date

Spring 2011

Pagination

x, 46 pages

Note about bibliography

Includes bibliographical references (page 60).

Rights

© 2011 John Benjamin Gaither, All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Subject Headings

Gas dynamics
Kinetic theory of gases

Thesis Number

T 9817

Print OCLC #

784152423

Electronic OCLC #

745905668

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