Mixed-Fidelity Model of Rotating Detonation Combustor

The rotating detonation combustor (RDC) is a type of pressure gain combustor (PGC) with potential for improved thermodynamic efficiency and geometric simplicity, facilitating easy integration into existing power systems and propulsion systems. The difficulty in controlling RDC lies in the chaotic and unpredictable nonlinear dynamics of detonation waves. The study aimed to develop a mixed-fidelity model to capture the governing physics of RDC at a reduced computational cost. The model consists of two domains. The quasi-one-dimensional (Q1D) domain captures the stratification between the reactant (R) and the product (P) layers. The two-dimensional (2D) domain extends axially above the Q1D domain, capturing the oblique shock waves that form behind detonation waves. In the Q1D domain, the interface between the R and P layers is updated according to an isentropic pressure equilibrium principle, which models the growth of the reactant refill region, and a shock sensor, which models the consumption of fresh reactants by the traveling detonation wave. The parameters allow the user to perform parametric studies of different geometries and initiation properties. The focus of the research was on studying the mode selection based on the initiation method in R-P domain, which governs the physical processes due to the existence of the Neutral Mach Line (NML). Co-rotating and counter-rotating waves were observed based on initial species distribution, suggesting the mode-selection can occur during combustor startup.