Laminar–turbulent transition in hypersonic boundary layers significantly influences heat transfer, skin friction, and flow separation. To examine the combined effects of shock wave–boundary layer interaction (SBLI) and adverse pressure gradients on boundary layer transition under hypersonic conditions, a flared cone–swept fin configuration was designed. High-fidelity transition data were obtained through wind tunnel experiments utilizing temperature-sensitive paint (TSP), temperature sensors, and high-frequency pressure sensors from PCB Piezotronics (PCB). TSP measurements revealed a triangular high-heat-flux region at the rear of the model, induced by the interaction between SBLI and the adverse pressure gradient. Temperature sensors provided precise wall heat flux, capturing a distinct “growth-decrease-regrowth” heat flux distribution pattern along the flared cone, highlighting the complex interplay between flow structures and transition phenomena. PCB sensors identified dominant instability modes, including low-frequency disturbances and second-mode instabilities. Furthermore, numerical simulations validated the wind tunnel results by reproducing the basic flow structures. This study presents the comprehensive wind tunnel dataset on transition for a complex configuration influenced by both SBLI and adverse pressure gradients, assessing the effects of Reynolds and Mach numbers on the flared cone–swept fin configuration. The findings offer valuable insights for transition prediction and thermal protection design in hypersonic vehicles with complicate fin–body interactions.

In our previous study, the transition behavior of a flared cone–swept fin configuration was investigated under an angle of attack (AoA) of 0°. To further explore the role of AoA in complex three-dimensional geometries with strong fin–body interactions, wind tunnel experiments were conducted at Ma = 9.3, Re = 1.36 × 10⁷/m, with AoA ranging from −6° to 6°. Global surface temperature distributions were obtained using temperature-sensitive paint (TSP), while localized heat flux and pressure fluctuations were captured using thin-film thermocouples and high-frequency pressure sensors. The results show that varying AoA shifts the location of high heat flux between the upper and lower surfaces of the flared cone and induces a switch from streamwise to separation vortices. The windward side exhibits stronger disturbance responses than the leeward side. The junction region between the flared cone and the near-horizontal surface is highly sensitive to AoA variations, consistently exhibiting pronounced second-mode instabilities. These findings provide experimental support for understanding transition mechanisms under the combined effects of shock/boundary layer interaction (SBLI), crossflow, and adverse pressure gradients, with implications for transition prediction and thermal protection system design.