Proc. of the 32nd International Symposium on Shock Waves (ISSW32) doi:10.3850/978-981-11-2730-4_0507-cd Copyright c  2019 ISSW32. All rights reserved. A Study of Integration of a Rotating Detonation Engine to a Waverider Forebody F.K. Lu, A.R. Mizener Aerodynamics Research Center, Mechanical and Aerospace Engineering Department, University of Texas at Arlington, Arlington, Texas 76019, USA P.E. Rodi Mechanical Engineering Department, William Marsh Rice University, Houston, Texas 77005, USA Corresponding Author’s name: franklu@uta.edu Abstract An ideal parametric analysis was performed by combining a waverider forebody generated by the osculating flowfield method and a second-order performance model for a rotating detonation engine. A sharp nose and a slightly convex forebody profile yielded the greatest pressure recovery and greatest installed engine performance. Engine performance improved with increasing Mach number, but propellant autoignition temperature limits may limit Mach numbers to less than 3.5. 1 Introduction The promise of detonations for aerospace propulsion has prompted attempts to realize such engine concepts for at least sixty years [1]. These attempts can be conveniently classified into a few main detonation engine genres as shown schematically in Fig. 1. The upper left shows an oblique detonation wave engine (ODWE) [2]. The incoming flow of premixed propellant exceeds the Chapman–Jouguet (CJ) speed which results in a steady oblique detonation wave forming over a sharp wedge indicated by the dotted line in the figure. To the right is a rotating detonation engine (RDE) which is generally considered steady although it is strictly not so [3, 4]. The curved arrow in the figure indicates a detonation wave traveling circumferentially in an annular chamber exhausting burnt products to the right. Due to the high frequency of operation of O(1–10) kHz, for application purposes it is considered steady although care must be exercised in interpreting the cyclic data. Below the RDE is a depiction of a pulsed detonation engine (PDE) where repeated, periodic ignition of the propellants causes detonation waves to propagate unidirectionally to the exit of the detonation tube [5, 6]. Design studies have indicated that a PDE must operate in the 50–200 Hz range for aerospace applications [7]. Finally, the lower left depicts linear detonation engine (LDE) which is a configuration that has not been well studied. It is the linear equivalent of the RDE in that detonation waves travel back-and-forth in a detonation chamber instead of circumferentially around one. This type of normal detonation wave process had been considered to be unstable and thus unsuitable for propulsion applications [2]. However, Wilson et al. [8] found that it is possible to allow the detonation wave to undergo a stable oscillatory motion if the incoming flow is at a sub-CJ Mach number. Depending on the length of the chamber, an LDE can operate at frequencies comparable to an RDE. There may be some further advantages in the LDE compared to the RDE in terms of scalability and ease of fueling but apparently not much research has been paid to this concept. The most commonly cited reason for pursuing detonation engines is the reduced en- tropy rise for the same ideal work produced as discussed in standard texts on combustion 2997