@article{cavanaugh_redding_narayanaswamy_bravo_murugan_2026, title={Analysis of a Continuously Variable Inlet and Isolator Design with Experimental, Computational, and Theoretical Comparison}, volume={1}, DOI={10.2514/6.2026-2189}, abstractNote={In the following investigation a novel continuously variable inlet and isolator design will be analyzed using experimental, computational, and theoretical approaches. This inlet and isolator design serves to expand operability limits and increase pressure recovery associated with airbreathing propulsion inlets. This is achieved with the application of a continuously deformable inner mold line (IML) surface. Both the theoretical model and provided experimental and computational results will serve to further analyze the effects of this variable panel deformation operation and characterize shock structure behavior. This isolator design is tested experimentally at Mach 3.8 using Schlieren imaging and pressure sensitive paints (PSP) and investigated computationally using a Spalart Allmaras Unsteady Reynolds Averaged Navier Stokes (URANS) solver in Eilmer. A quasi 1-D analysis will be adopted to form the basis of the theoretical portion of this analysis. This analysis will be focused on the internal flow within the isolator section containing the continuously deformable surface. This comparison will serve to investigate the effectiveness of these traditional theoretical approaches for evolving and complex inlet and isolator geometries.}, author={Cavanaugh, Emma C. and Redding, Jeremy and Narayanaswamy, Venkateswaran and Bravo, Luis and Murugan, Muthuvel}, year={2026}, month={Jan} }
 @article{redding_cavanaugh_bravo_murugan_narayanaswamy_2025, title={Investigation of scramjet inlet unstart/restart behavior induced by high angle of attack and dynamic isolator camber motion}, volume={37}, url={https://doi.org/10.1063/5.0271076}, DOI={10.1063/5.0271076}, abstractNote={This study employs high-fidelity simulations, benchmarked with wind tunnel experiments at Mach 3.9, to investigate how pitching maneuvers influence unstart in a planar scramjet inlet with a Mach 2.5 shock-on-lip design and a contraction ratio of 2.14. Simulations utilize the Spalart–Allmaras unsteady Reynolds-averaged Navier–Stokes turbulence model to analyze unstart onset across two pitch rates (10°/s and 100°/s) over an AoA (angle of attack) range of 0°to 10°. Results indicate that unstart onset correlates with a rapid rise in exit pressure and shock detachment along the lower leading edge, with lower pitch rates producing significantly higher exit pressures. These findings highlight the sensitivity of inlet stability to the transient aerodynamics of the pitching maneuvers. A dynamic adjustment of the isolator area is introduced just before the unstart onset to evaluate the potential of this approach for unstart mitigation. This strategy enabled shock reformation and direct regulation of outlet pressure, demonstrating the potential for variable-camber inlet-isolator systems in maintaining performance under off-design conditions. In addition to physical observations, an analytical approach is presented to predict the re-acceleration of the flow due to the time rate of change of area in the isolator. An excellent alignment between the analytical equation and the simulated results is observed, indicating a useful relation for insight into inlet/isolator unstart–restart behavior, with application to future wind tunnel tests, control theory implementation, and maneuver limit studies.}, number={6}, journal={Physics of Fluids}, author={Redding, Jeremy and Cavanaugh, Emma and Bravo, Luis and Murugan, Muthuvel and Narayanaswamy, Venkat}, year={2025}, month={Jun} }