Keywords
combustion, chemical kinetics, natural gas, methane
Abstract
In recent years, the space travel industry has grown exponentially, resulting in the need for a low-cost, efficient rocket engine fuel. As such, there has been renewed interest in utilizing liquid natural gas (LNG) as it is less likely to soot than kerosene-based fuels and has widespread availability and low cost of use as compared to the traditional RP-X and even liquid methane (LCH4) fuels due to the reduced need for refinement. However, current literature does not fully cover varying blends of natural gas and the effects that impurities have on natural gas/methane fuels, with most studies being confined to low-pressure applications. Therefore, new experimental ignition delay time measurements at rocket engine relevant pressures are essential to ensure current chemical kinetic models capture the ignition behavior at these elevated conditions and to determine the optimal purity levels for a reliable, cost-efficient, aerospace-grade LCH4/LNG fuel. The current work explores various blends of natural gas/methane fuel with various impurities, including higher hydrocarbons as well as nitrogen-carriers. A shock tube study was carried out to study the ignition delay times and carbon monoxide time histories of these natural gas blends utilizing chemiluminescence and laser absorption spectroscopy at 20, 50 and 100 atm over temperatures ranging from 1400-1700 K and at an equivalence ratio of 1. The experimental data was then compared to two different chemical kinetic mechanisms: the industry-standard GRI 3.0 and the in-house UCF 2022. The data is used to improve chemical kinetic mechanisms and modeling of LNG fuels for rocket engine applications.
Completion Date
2024
Semester
Summer
Committee Chair
Vasu, Subith
Degree
Doctor of Philosophy (Ph.D.)
College
College of Engineering and Computer Science
Department
Department of Mechanical and Aerospace Engineering
Degree Program
Mechanical Engineering
Format
application/pdf
Identifier
DP0028557
URL
https://purls.library.ucf.edu/go/DP0028557
Language
English
Release Date
8-15-2027
Length of Campus-only Access
3 years
Access Status
Doctoral Dissertation (Campus-only Access)
Campus Location
Orlando (Main) Campus
STARS Citation
Baker, Jessica, "Fundamental Experimental Tests and Modeling of LOx/CH4 Engines at High Pressures" (2024). Graduate Thesis and Dissertation 2023-2024. 352.
https://stars.library.ucf.edu/etd2023/352
Accessibility Status
Meets minimum standards for ETDs/HUTs
Restricted to the UCF community until 8-15-2027; it will then be open access.