A Multiphysics Approach to Radio Frequency Modeling of Ablators in Ionized Hypersonic Flow

ATA Engineering, Inc., (ATA) proposes to develop and demonstrate a multiphysics framework for the radar cross-section (RCS) analysis of an ablating hypersonic vehicle in an ionized plasma flow field. ATA has developed a software toolset, known as the Multiphysics Engine, capable of modeling many of these hypersonic phenomena. It couples state-of-the-art solvers for CFD (Loci/CHEM), ablation (CHAR), and mechanical response (Abaqus) and is capable of simulating the ablation response of advanced thermal protection system (TPS) materials like composite carbon-carbon in hypersonic environments. In the proposed effort, the project team will enhance the Multiphysics Engine by adding models to accurately and efficiently simulate ionized plasma and incorporate a computational electromagnetics (CEM) solver into the workflow for RCS prediction. \n\n The Phase I effort will focus on improving the plasma dynamics modeling capability in Loci/CHEM and incorporating a new coupling between Loci/CHEM and the CEM solver to enable RCS prediction. The computational efficiency of plasma simulations will be improved by adapting ATA’s Damköhler In-Situ Targeted Adaptive Numerical Thermochemistry (DISTANT) finite-rate chemical reaction model to nonequilibrium and ionized flows. The plasma dynamics modeling capability will be preliminarily validated and the advantage provided by DISTANT quantified by comparing predictions to experimental data from open literature. The new RCS modeling capability will be demonstrated by estimating the RCS for a test body. In Phase II, ATA will conduct more rigorous validation activities and implement additional enhancements, including developing a new magnetohydrodynamics (MHD) capability for Loci/CHEM to model ionized hypersonic flow in the presence of electromagnetic fields. The resulting toolset will deliver a new capability for GEOINT analysis of hypersonic systems via an integrated means of modeling the influence of ionized flow around an ablating hypersonic vehicle on the observable RCS, including the effect of plasma flow control devices.