An ADT-Based Local RBF Method for Interface Data Transfer in Fluid-Thermal-Structural Coupling

During hypersonic flight, spacecraft face severe aerothermal issues. The aerothermodynamic environment not only affects the structure of the vehicle but, in turn, the structural response influences the aerothermodynamic environment, resulting in fluid-thermal-structural coupling. A coupling framework is developed to quickly predict the fluid-thermal-structural effects using engineering algorithms for aerodynamics and aerothermal, along with Abaqus software for structural responses and temperature distributions. Loose coupling is achieved through data transfer. To address the mesh interface mismatch, an improved radial basis function (RBF) method is proposed. Utilizing an alternating digital tree (ADT) data structure, the nearby source points around each target point are quickly identified as local control points for subsequent RBF interpolation, which significantly improves efficiency while ensuring interpolation accuracy. Additionally, based on an idealized flight trajectory, the surface temperature and radiative equilibrium temperature of the spaceplane are determined, validating the effectiveness of the rapid fluid-thermal-structural coupling framework.