Numerical Analysis of Chamber Wall Thermal Effects and Heat Flux in a Rotating Detonation Rocket Engine

Rotating detonation rocket engines (RDREs) have the potential to achieve higher performance and efficiency than conventional rocket engines. High-fidelity simulations of RDREs are influential in advancing this technology because of the limited availability of experimental measurements. Most RDRE simulations use an adiabatic boundary condition for the chamber walls. In this study, we show the improvements that isothermal wall boundary conditions can provide to RDRE simulations compared with adiabatic boundaries. Results show that using an isothermal wall boundary condition can improve RDRE simulations by accounting for thermal losses, reducing the overprediction of chamber pressure, net thrust, and specific impulse compared with experimental data. The modeled heat losses from the combustion flow field account for up to 7% of the thrust overprediction typically seen when adiabatic simulations are compared with heat-sink experiments. The average wall heat flux is estimated by calculating the energy difference between the adiabatic and isothermal wall simulations. Results suggest average heat fluxes to the chamber walls are on the order of 7 MW/m2. The contributions of this work provide a framework to improve RDRE modeling accuracy utilizing isothermal wall boundary conditions and establish a methodology to estimate RDRE heat flux, which is critical to the design of thermal management systems.