This study presents a comprehensive investigation of conjugate heat transfer (CHT) phenomena arising from shock wave–boundary layer interactions in a Mach 2.5 supersonic flow field. Advanced computational fluid dynamics (CFD) simulation platforms were employed to conduct a rigorous multi-physics numerical analysis at the critical solid–fluid thermodynamic interface, leveraging state-of-the-art numerical discretizations and turbulence modeling techniques. The fluid was modeled as an ideal gas, and the material of the flat plate on which the interaction takes place was taken as an isotropic material. A total simulation time of \(500\mu s\) was considered, and the CHT analysis showed good agreement with reference wall heat-flux data, validating the approach. The study further integrated surface arc plasma actuator (SAPA)-based flow control strategies to evaluate their impact on separation behavior, drag reduction, and surface thermal loading. The results demonstrate that SAPA actuation significantly modifies the separation dynamics and local heat flux characteristics. The influence of material thermal conductivity on separation reduction was assessed, revealing that low-conductivity materials like Macor exhibit superior flow control effectiveness. Additionally, comparisons between single- and multi-SAPA configurations revealed that distributed, repeated pulse actuation not only enhances time-dependent drag reduction but also yields higher propulsive energy savings. Overall, this work establishes a validated and robust CHT framework to explore the dual aerodynamic and thermal impacts of SAPA actuation, offering new insights into active flow control for high-speed aerospace applications.
