A study of a supersonic capsule/rigid disk-gap-band parachute system using large-eddy simulation

The aerodynamic performances and flow features of the capsule/rigid disk-gap-band(DGB) parachute system from the Mach number 1.8 to 2.2 are studied. We use the adaptive mesh refinement(AMR), the hybrid tuned center-difference and weighted essentially non-oscillatory(TCD-WENO) scheme, and the large-eddy simulation(LES)with the stretched-vortex subgrid model. The simulations reproduce complex interaction of the flow structures, including turbulent wakes and bow shocks, as well as bow shocks and expansion waves. The results show that the calculated aerodynamic drag coefficient agrees well with the previou simulation. Both the aerodynamic drag coefficient and the aerodynamic drag oscillation of the parachute system decrease with the increase of the initial Mach number of the fluid. It is found that the position and angle of the bow shock ahead of the canopy change as the Mach number increases, which makes the flow inside the canopy and the turbulent wake behind the canopy more complex and unstable.