Design and Operation of a Radial Rotating Detonation Engine

• Published in: Journal of propulsion and power 2019-11, Vol.35 (6), p.1143-1150
• Main Authors: Huff, Riley, Polanka, Marc D, McClearn, Michael J, Schauer, Frederick R, Fotia, Matthew L, Hoke, John L
• Format: Article
• Language: English
• Subjects: Detonation; Equivalence ratio; Mass flow rate; Modular design; Modular units; Nozzles; Rotation; Superchargers; Turbines; Turbogenerators
• ISSN: 1533-3876; 0748-4658; 1533-3876
• DOI: 10.2514/1.B37578

Recently, there has been a need for compact rapid-response power generators on aircraft. A novel solution to this problem comes in the form of coupling a rotating detonation engine (RDE) with a turbine generator. To improve power density, a new type of RDE, referred to as the radial RDE, has been developed. This design was based on a disk-shaped device within which reactants flow from the outer radius, detonate, and exit the inner radius. This was coupled into a compact centrifugal turbocharger turbine to extract the power. The first step in this process was to design a modular unit that would enable an understanding of the parameters that enable detonation in this type of device. Control over the throat area, channel area, and nozzle exit area enabled a range of area ratios to be evaluated. Other primary controls included the mass flow and equivalence ratio within the device. Initial results confirmed detonation operation between mass flow rates of 0.139–0.656  kg/s at equivalence ratios ranging from 0.67 to 1.10. Operating frequencies and wave speeds are reported. Lastly, high-speed images of the exhaust as well as pressure traces are shown as confirmation of detonation, and reveal multiwave operation for various conditions.