Synthetic Laser Measurements in Rotating Detonation Rocket Engine Simulations

Recent advancements in laser diagnostics have made it possible to take temporally-resolved measurements of temperature, pressure, and species composition in rotating detonation rocket engine flowfields. These temporally-resolved measurements are well-suited to use with simulation data, but such studies need an approach that accurately relates simulation data with laser measurements. In this study, two methodologies are presented for calculating laser absorption spectroscopy measurements using simulation data: one based on an idealized measurement, and another using the flowfield to model laser absorption. Both methodologies are then used to relate high-fidelity LES to experimental laser absorption spectroscopy measurements of the RDRE configuration used for the AIAA MVP workshop. It is shown that the same temporally-resolved flow features are observed in both the simulation and experimental exhaust flowfields, and the simulation is used to demonstrate that experimentally-observed peaks in exhaust CO correspond fuel-rich regions in the injection mixing field.