ORCID

https://orcid.org/0009-0007-0101-1261

Keywords

Scramjet, Hypersonics, Novel Ignition System, High-speed Air-breathing propulsion, Experimental Testing, Liquid-fueled device

Subject Categories

Aerospace Engineering | Mechanical Engineering | Propulsion and Power

Abstract

As global demands for supersonic and hypersonic flight heighten, high-speed air breathing propulsion technologies stand out as a worthwhile direction to overcome many of the limitations that turbomachinery-based engines face at supersonic speeds. Air breathing propulsion concepts are attractive for their geometrical simplicity, using supersonic incoming air to provide compression. Scramjet flight vehicles operate within the hypersonic flight regime and have been a global research topic, especially in the 21st century, for defense and combined cycle engine architectures. As scramjet technology continues maturing towards widespread use, efforts have converged on liquid hydrocarbon fuels for storage, range, and operational benefits. Flight vehicles must maintain strict mass and volume budgets while ensuring the safety of all internal components at the harsh operating conditions experienced at hypersonic speeds within the atmosphere. Innovations at the subsystem level are critical towards optimization of scramjet technology, especially the ignition device used to initiate combustion within the vehicle. The work of this dissertation aims to develop a novel liquid-fueled ignition device that focuses on providing robust ignition over a wide range of non-favorable operating conditions with emphasis on delivering a packaged subsystem for plug and play use within current combustor geometries. Development of this ignition device follows an iterative approach for optimization, beginning with comprehensive standalone tabletop validation, followed by evaluation within a scramjet ground test facility at simulated flight conditions. Ignition performance is compared to two other conventional ignition devices in scramjet literature: an automotive spark plug, and a pulse detonation igniter. Finally, a fundamental understanding of scramjet ignition mechanism is detailed from the lens of ignition delay and cavity flame spreading to provide a basis for future development of cavity-based scramjet ignition devices.

Completion Date

2026

Semester

Summer

Committee Chair

Ahmed, Kareem

Degree

Doctor of Philosophy (Ph.D.)

College

College of Engineering and Computer Science

Department

Mechanical and Aerospace Engineering

Format

PDF

Document Type

Dissertation

Language

English

Download

Share

COinS
 

Accessibility Statement

This item was created or digitized prior to April 24, 2027, or is a reproduction of legacy media created before that date. It is preserved in its original, unmodified state specifically for research, reference, or historical recordkeeping. In accordance with the ADA Title II Final Rule, the University Libraries provides accessible versions of archival materials upon request. To request an accommodation for this item, please submit an accessibility request form.