Aerodynamic and Dynamic Analysis of a Hypersonic Waverider with a Coupled Dynamic–Thermodynamic Model

ABSTRACT The demand for ultrafast transportation and strategic defense systems has intensified research on air-breathing hypersonic vehicles powered by scramjet engines. These systems face critical technological challenges, particularly the strong coupling between propulsion and flight dynamics. Current simulation frameworks often oversimplify engine behavior, neglecting effects such as heat transfer, supersonic combustion, and compressible flow. To address this gap, this work develops an integrated simulation model that couples six-degree-of-freedom rigid-body flight dynamics with a thermodynamic model of a scramjet engine. The framework incorporates atmospheric and mass variation models, aerodynamic coefficients based on engineering methods, and full-actuator dynamics. Control laws are implemented through inner-loop stabilization and outer-loop autopilot logic. Simulation results indicate that the vehicle maintains aerodynamic stability from Mach 5 to 10, with maximum efficiency near Mach 8. Lift, drag, and pitching moment coefficients show consistent compressibility effects, while elevon deflections provide effective control authority across the hypersonic envelope. Dynamic mode analysis reveals lightly damped open-loop behavior typical of hypersonic configurations, especially in roll and pitch, which are stabilized by control laws.