The Effect of Reefing Time on the Damage Process of the Supersonic Parachute

Parachutes have been widely used in the supersonic deceleration process of Mars probes due to its high deceleration efficiency. However, the canopy damage may occur and lead to the collapse of parachute under high dynamic load. To avoid parachute damage, the reefing method is commonly used to delay the inflation thus reduce the dynamic load. Numerical simulations were conducted on the inflation process of supersonic parachute using the ALE (Arbitrary Lagrange Euler) method. In order to investigate the influence of reefing time on the damage propagation process of parachute, the failure of canopy was simulated by adopting MAE (Material Add Erosion) model. The numerical model can effectively simulate the canopy shape and dynamic load during the inflation process. On this basis, the interactions between flow and canopy structure during the damage propagation process was studied, and the influence of the reefing time on the damage propagation process was analyzed. Results showed that the airflow through the canopy damaged zone led to the asymmetry of the flow, and this led to the stress concentration and the successive damage in multiple places on canopy surface. With the increasing reefing time, the dynamic pressure when canopy begins to re-inflate decreases, the stress near the damaged zone increases more slowly and so does the damage propagates; therefore, the canopy damage area decreases.