A Simple Model for Rotating Detonation Rocket Engine Sizing and Performance Estimates

Daniel E Paxson; Hugh D Perkins

NASA NTRS · 20205010859

A Simple Model for Rotating Detonation Rocket Engine Sizing and Performance Estimates

Abstract

A Rotating Detonation Rocket Engine (RDRE) model is described which characterizes the device as an essentially infinite number of circumferentially arranged, sequentially firing pulse detonation engine (PDE) tubes. The PDE tubes are in turn treated as lumped-parameter chambers, each of which executes a dynamic (i.e. time dependent) Atkinson cycle with an allowance for a finite Mach number during the refill portion of the cycle. The formulation results in several free parameters which are used to essentially tune the model such that it closely matches higher fidelity computational fluid dynamic RDRE simulations in terms of performance, flow rates, etc. The simplicity of the model allows for straightforward combination with component models (e.g. turbopumps, cooling jackets, etc.) as well as implementation within larger vehicle simulations. Such capability allows for realistic mission analyses and benefits studies which will help to determine the best application for the RDRE concept.

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Daniel E Paxson, Hugh D Perkins. A Simple Model for Rotating Detonation Rocket Engine Sizing and Performance Estimates. https://ntrs.nasa.gov/citations/20205010859

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