Assessment of Heat Flux Driven by Structurally Informed Deformations at Mach 6

The design of hypersonic vehicles requires a thorough understanding of how intense aerothermal loads cause structural panel deflections that alter surface heating. This study experimentally investigates this phenomenon by testing statically deflected panels at Mach 6 in the U.S. Air Force Research Laboratory Ludwieg Tube. Two structurally informed deformations (a simple single mode and a complex multimode), derived from prior fluid/thermal/structural interaction data, were compared against a baseline flat plate. Although high-speed schlieren imaging revealed that the deformations did not significantly alter boundary-layer instability modes, infrared thermography showed a significant impact on heat transfer. Notably, both deformed geometries delayed the onset of increased heating from boundary-layer transition, reducing the total integrated heat load at high Reynolds numbers compared to the flat plate. Conversely, at lower Reynolds numbers, localized flow compression from the panel curvature increased the heat load. Finally, two predictive models for estimating heat flux on arbitrarily deformed surfaces were developed and validated against the experimental data, demonstrating a potential path toward robustly modeling these complex effects in vehicle design.