Aerodynamic Characteristics of Cruciform Parachute with an Asymmetric Configuration of Ropes

In this study, an aerodynamic control scheme was proposed based on an asymmetric configuration of the ropes of a cruciform parachute to provide the lateral aerodynamic control forces required for it. Wind tunnel tests were conducted to confirm that this scheme could generate a lateral aerodynamic force for the cruciform parachute that was approximately 24% of the axial force. The deployment of a cruciform parachute under a subsonic flow regime was simulated by coupling the lattice Boltzmann method with a structural model. The shape of the canopy obtained from the coupled calculations was in good agreement with that determined based on the results of the wind tunnel test. The results of both showed that the cruciform parachute tilted along the direction of the shortened ropes under the combined action of the asymmetric configuration and incoming flow. This led to a difference in the lateral pressure on the canopy that led to the generation of lateral aerodynamic forces, which were linearly related to the reduced length of the ropes, and increased as their length decreased.