Numerical Study on Aerodynamic Performance of Mars Parachute Models with Geometric Porosities

The supersonic flows around rigid parachute-like two-body configurations are numerically simulated at Mach number of 1.978 by solving three-dimensional compressible Navier-Stokes equations, where the two-body model consists of a capsule and a canopy, and a geometric structure (i.e., gap) is located on the canopy surface. The objective of this study is to investigate the effects of gaps with different porosities and positions on the aerodynamic performance of supersonic parachute. The complicated periodic aerodynamic interactions between the capsule wake and canopy shock occur around these two-body models. From the formation of canopy shock and drag coefficient variation, the cycled flow structures can be divided into three types:(1) narrow wake period, (2) open wake period, and (3) middle wake period. In addition, it was found that the geometric gaps have no obvious influences on the flow modes. However, compared with models with different gap positions, the two-body model with an upper gap (gap is close to the canopy vent, UG model) has a smaller drag coefficient fluctuation and better lateral stability. On the other side, the increase of porosity has a more significant impact on UG models.