Development-Fluid-Dynamics-Based Aerothermoelastic Simulation Capability with Application to Flight Vehicles

摘要

Aerodynamic heating on structural surfaces plays an important role in the aeroelastic stability of flight vehicles, particularly in a high-temperature environment. The thermal effects of high-speed flow, obtained from a heat-conduction analysis, at the end of an unsteady time step are incorporated in the model solution, which in turn affects the unsteady flow arising out of interaction of the elastic structure with the air. This paper describes the development, implementation, and application of a highly integrated computational-fluid-dynamics-based aerothermoelastic analysis capability and the resulting code. The associated methodology employs the common finite element discretization for both fluid and structure disciplines using unstructured grids. An aeroelastic matrix formulation that uses a transpiration technique in lieu of aerodynamics mesh updating affects an efficient and accurate simulation of the aerothermoelastic phenomenon. The first example problem of a cantilever wing demonstrates the possible severity of thermal effects on a flutter mechanism. The second example of the X-43 hypersonic flight vehicle shows that the current procedure and the code can effectively solve complex practical problems with moderate computational resources. The accuracy and relative efficiency of the computational-fluid-dynamics and structural solutions are verified using actual flight and ground vibration tests.