Design and Construction of a Detonation Tube for Use as a Non-Intrusive Diagnostics Testing Apparatus
Renewed interest in the development of detonation propulsion systems for both air-breathing and rocket applications has led to a need for improved diagnostic techniques and tools for the determination of detonation environment properties and flow mechanics. The need for quantitative, time-resolved, and detailed spatial resolution is vital to hastening the development of these devices and their viability as a more efficient propulsion system in the future. To that end, the development of a linear detonation tube was undertaken at the University of Texas at San Antonio's (UTSA) Hypersonic Laboratory, specifically for the purpose of expanding the capabilities of non-intrusive methods. The apparatus maintains a continuous 1.5-inch inner diameter through its 6-foot length, which consists of a visually clear 2-foot section for chemiluminescence image capturing and contains a total of fourteen instrumentation ports. The detonation tube is resistant to chemicals and is designed to utilize a wide range of fuel types. Nine initial tests were conducted on the system using a 3:1 ethylene to oxygen mix at an initial pressure of 3.0 psia. Results from these tests confirm an operational capability of generating consistent detonations at Mach 7.05 with this mixture. Velocity measurements are found to be within 3% of Chapman-Jouguet calculations.