Analysis of Flow-, Thermal-, and Structural-Interaction of Hypersonic Structures Subjected to Severe Aerodynamic Heating.

摘要

Over the past two years a unique collection of algorithms have been developed for the analysis of hypersonic structures subjected to severe aerodynamic heating. These algorithms employ adaptive computational methods to resolve many of the complex structural and flow features such as nonelastic, large, time-dependent structural deformations, shock interaction boundary layers and shock interactions. Local error estimates were used to evaluate the quality of the computed solutions and subsequently optimize the structure of the grids to deliver a specified level of accuracy with a minimum of computational effort. In addition, implicit/explicit solution algorithms for the fluid modeling were employed which exploit the speed and simplicity of explicit methods and the stability of implicit methods. Zoning techniques for automatically selecting the implicit and explicit zones were studied with optimization of the computational effort as the central goal. The modeling of the structural problems incorporated a version of the Bodner-Partom constitutive model for time-dependent viscoplastic materials. During the course of this study this model was extended to include a damage parameter which was treated as an additional internal state variable. A number of validation cases were run to test the various components of the package and prepare for the experimental verification which was planned for year three. Keywords: Hypersonic flight, Viscous compressible flow. (kr)