Summary of Recent Research on Detonation Wave Engines at UTA
A survey of recent research at UTA on detonation waves related to propulsion is presented in this paper. A brief historical review of the early pulse detonation engine (PDE) research at UTA is provided to lay the background for the development of a large-scale PDE Ground Demonstrator. Also current activities related to the development of rotating detonation wave engines (RDE) are reviewed. System integration studies for both PDE- and RDE-based propulsion systems are summarized, followed by a brief description of two programs focusing on application of detonation waves to hypersonic flow simulation and power generation.
Pressure History at the Thrust Wall of a Simplified Pulse Detonation Engine
Gas dynamics in a simplified pulse detonation engine (PDE) was theoretically analyzed. A PDE was simplified as a straight tube with a fixed cross section. One end of the tube was closed, namely, this end was the thrust wall, and the other end was open. A detonation wave was initiated at the closed end and simultaneously started to propagate toward the open end. When the detonation wave broke out from the open end, a rarefaction wave started to propagate from the open end toward the closed end. This rarefaction wave was reflected by the closed end. By considering this rarefaction wave to be self-similar in the analysis of the interference between this rarefaction wave and its reflection from the closed end, we analytically formulated the decay portion of the pressure history at the closed end (thrust wall) without any empirical parameters. By integrating the obtained pressure history at the thrust wall with respect to time, important performance parameters of a PDE were also formulated. The obtained formulas were compared with numerical and experimental results and agreed with them very well.
Technical Notes Exergy Analysis of a Pulse Detonation Power Device
Recent research has been developed in thermodynamic analysis of pulse detonation engines. However, the focus of contemporary work is on thrust production for propulsion systems. The present work develops an exergy analysis of a pulse detonation power device. The objective of this analysis is to quantify the efficiency, in terms of availability, of a power device operated by detonation. This study considered the fuel availability and the losses in the system. Losses are due to irreversibilities during processes and due to availability transfer. The Second Law or exergetic efficiency was computed based on the fuel availability. The device modeled here embraces a low pressure compressor, a check valve, a detonation chamber, a two stage turbine and a generator. The results are then compared with the exergetic efficiency applied to deflagration systems. Data for detonation and deflagration were obtained from C.E.A. code (McBride and Gordon, 1994), using two different hydrocarbon fuels: methane (CH4) and propane (C3H8). The results of this study show that detonation is a much more energetic process than deflagration, and the exergy analysis makes clear that this device is efficient for power generation.