Dynamics of Detonation Wave–Core Combustion Interaction in a Flow-Through Rotating Detonation Combustor

This study experimentally investigates detonation wave–core flow interactions in a flow-through rotating detonation combustor (FT-RDC). Two test campaigns were conducted: 1) OH–planar laser-induced fluorescence (OH-PLIF) visualizations using a [Formula: see text] backward-facing step (BFS2) configuration and 2) simultaneous aft and side [Formula: see text] chemiluminescence imaging. The first chemiluminescence subset used BFS2 with both RDC and core fueled by ethylene–air, while the second used a [Formula: see text] BFS (BFS1) with hydrogen–air fueling in the RDC and ethylene–air in the core. These tests focused on characterizing detonation–core interactions and developing novel postprocessing methods to quantify them. The effects of varying BFS geometry and using dissimilar fuels were examined to assess their influence on core penetration and detonation behavior. Visualizations from both PLIF and chemiluminescence provided detailed insight into detonation structure and interaction dynamics, supporting model validation and the identification of critical operating parameters. Consistent trends across diagnostics highlight the robustness of both techniques. The BFS2 configuration exhibited a bimodal interaction pattern, while BFS1 showed a more unified structure, suggesting that step geometry significantly influences interaction morphology. Ultimately, the spatial characteristics of detonation–core interactions are shaped by a combination of step height and core flow conditions, with implications for future RDC design and operability.