Development of Injector-Coupled and Simplified Zero-Dimensional Performance Models for Rotating Detonation Engines

Rotating Detonation Engines (RDE) have attracted significant interest in the propulsion community due to their potential for higher thermodynamic performance and reduced weight. With this growing interest, there is an opportunity to develop a simple zero-dimensional (0D) analysis tool, analogous to NASA’s Chemical Equilibrium with Applications (CEA), to assist in rapid RDE design. However, RDE blowdown behavior is typically highly sensitive to injector dynamics and plenum pressures, complicating simplified analysis. To address this, this study conducts a comparative analysis between two 0D performance models: an injector-coupled model that accounts for inflow dynamics and plenum pressurization, and a simplified, decoupled model that operates under “CEA-like” assumptions. The models are evaluated across a range of injector area ratios and stagnation pressures. Results indicate that while the injector-coupled model is necessary when injector stiffness or plenum pressurization is a key metric, the simplified model predicts cycle-averaged performance metrics (such as specific impulse) with less than 1% deviation. Consequently, the simplified tool is validated as an effective, boundary-condition-agnostic approach for preliminary RDE design and performance estimation.