High-fidelity simulation and low-order analysis for planetary descent investigation of capsule-parachute interaction

Abstract. The project focuses on characterizing the unsteady dynamics of the parachute-capsule system during the descent phase of planetary entry in a supersonic flow regime. Currently, Large-Eddy Simulation, coupled with an Immersed-Boundary Method, is utilized to examine the time-evolving flow behavior of a rigid supersonic parachute trailing behind a reentry capsule as it descends through the Martian atmosphere. The flow is simulated at Ma=2 and Re=10⁶. A massive GPU parallelization has been utilized to enable a high-fidelity resolution of the turbulent structures in the flow, essential for capturing its dynamic behavior. We demonstrate through low-order modeling of the unsteady turbulent wake of the capsule that low-frequency fluctuations within the wake are the primary trigger for flow instability in front of the canopy volume. Proper-Orthogonal Decomposition is utilized to investigate the system dynamics and analyze how various turbulence contributions influence the phenomenon.