Fluid-Structure Interaction Simulation and Accurate Dynamic Modeling of Parachute Warhead System Based on Impact Point Prediction

To predict a parachute-warhead system's dynamic characteristics and impact point, numerical methods are used to comprehensively predict the large deformations of the parachute during the opening process and the impact point of the system in the terminal landing phase. Fluid-structure interaction simulations based on the arbitrary Lagrangian-Eulerian method are used to study the Disk-Gap-Band parachute's inflation behavior and provide the parachute's aerodynamic parameters at steady state. Based on the obtained aerodynamic data, a nine-degree-of-freedom dynamic model of the parachute-warhead system was established, which was used to predict the landing area of the system by calculating the falling trajectory. Based on the established model, an online impact point prediction program was developed. Finally, the effectiveness and accuracy of the methods were verified by airdrop experiments. The results showed that the methods for the parachute-warhead system modeling during the inflation and terminal descent phases could effectively predict its dynamic characteristics, which could be further applied for precision airdrop missions.