Review of propulsion applications and numerical simulations of the pulsed detonation engine concept

Abstract

Here we review experimental and computational studies of the pulsed detonation engine concept (PDEC) and present results of our recent numerical study of this concept. The PDEC was proposed in the early 1940s for small engine applications; however, its potential was never realized due to a complicated, unsteady operation regime. In this study, we demonstrate the use of current advances in numerical simulation for the analysis of the PDEC. The high-thrust/engine volume ratio obtained in our simulations demonstrates promising potential of the pulsed detonation engine concept. IntroductionE ARLY developments of engine technology leading to practical propulsion engines were almost completely associated with steady-state engine concepts. Unsteady concepts, which initially appeared promising, never evolved from the conceptual state and have remained for the most part unexplored. The early work in unsteady propulsion suffered from a lack of appropriate analytical and design tools, a condition which seriously impeded the advancement of the unsteady concepts to a practical stage.In this paper, we review the historical development of unsteady propulsion by concentrating on the particular concept of the intermittent detonation engine, and discuss current research activities in this area. A review of the literature 1 ' 24 reveals that a significant body of experimental and theoretical research exists in the area of unsteady propulsion. However, this research has not been extended to the point where a conclusive quantitative comparison can be made between impulsive engine concepts and steady-state concepts. For example, the analysis given in Refs. 8-11 of the performance of a detonation engine concept includes neither frequency dependence nor analysis of losses due to multicycle operation. A new generation of analytical and computational tools exists today and allows us to revisit and analyze such issues with a high degree of confidence. Numerical simulation has developed to the state where it can now provide time-dependent two-and three-dimensional modeling of complex internal flow processes 20 ' 24 ' 25 and will eventually result in tools for systematically analyzing and optimizing engineering design. In addition to a review of applications of the pulsed detonation engine concept (PDEC), we will report results of a numerical study of an air-breathing detonation engine. This study was performed using new unsteady computational fluid dynamics (CFD) tools that we will also describe.Our paper is structured as follows: 1) historical review of the pulsed detonation development efforts; 2) description of the basic phenomenology of the air-breathing pulsed detonation engine concept; 3) description of the mathematical formulation and new numerical scheme used to simulate the problem; 4) discussion of the simulation results; and 5) conclusions. Constant-Volume CombustionFrom the very early development of jet-propulsion engines, it was known that an engine based on a constant-volume combustion process achieves higher thermodynamics ef...

Experimental and numerical investigation of an 8-cm valveless pulsejet

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Performance Measurements of Multicycle Pulse-Detonation-Engine Exhaust Nozzles

“…4,6,7 These promising results have led to many PDE applications being proposed. For example, it has been suggested that PDEs can be used as cost-effective replacements for small gas-turbine engines, as potential replacements for combustors on existing large-scale gas turbines, or as thrust augmenters.…”

Detonation Waves and Propulsion

“…Our knowledge of detonations is almost exclusively based on propagating waves and almost all of the discussion about steady detonation wave engines is pure speculation. In this paper, the focus will be on steady waves although it should be pointed out that propagating detonations have been proposed as components in intrinsically unsteady wave engines (Eidelman et al 1991, Voytsekhovskiy et al 1964.…”