Computational framework for Launch, Ascent, and Vehicle Aerodynamics (LAVA)

Abstract

The Launch Ascent and Vehicle Aerodynamics (LAVA) framework, developed at NASA Ames Research Center, is introduced. This technology originated from addressing some of the key challenges that were present during the re-design of the launch infrastructure at Kennedy Space Center. The solver combines Computational Fluid Dynamics (CFD) capabilities with auxiliary modules, such as Conjugate Heat Transfer (CHT) and Computational Aero-Acoustics (CAA). LAVA is designed to be grid agnostic, i.e., it can handle block-structured Cartesian, generalized curvilinear overset and unstructured polyhedral grids either as stand-alone mode or by coupling different grid types through an overset interface. A description of the spatial discretizations utilized for each grid type, along with the available explicit and implicit time-stepping schemes, is provided. The overset grid coupling procedure for Cartesian and unstructured mesh types, as well as the CHT and CAA capabilities is discussed in some detail. Several NASA mission related applications are also presented to demonstrate the capabilities for large-scale applications, such as pressure, thermal and acoustic analyses of the geometrically complex launch environment, steady and unsteady ascent aerodynamics, plume-induced flow separation analyses of heavy lift launch vehicles and aeroacoustic applications. In addition, two validation cases related to NASA aeronautics applications are presented: the 1st AIAA Sonic Boom Prediction Workshop test cases and a computational study of slat noise.