Research On Inflation And Performance Of Parachute In Mars Environment

This paper carries out theory analysis and study in numerical simulation arming at the process of parachute inflation in Mars exploration, and the knowledge of structural mechanics and computational fluid dynamics has been applied to the establishment of Porous Media Model of canopy and fluid field model around canopy. Coupled the two models, the dynamic numerical simulation is carried though by adopting method of fluid-structure coupling theory during parachute opening process. Parachute opening conditions and service behavior are analyzed in the work environment of low density, supersonic velocity and low dynamic pressure.Fluid-structure coupling Mathematical model is set up during the process of parachute work, and the methods which structural calculation, flow field calculation and fluid-structure coupling calculation adopt , are introduced in detail. Numerical simulation method used in solution fluid-structure coupling is established. The porous jump boundary conditions are introduced in flow fluid model, and canopy porosity is simulated, and ventilation property of parachute material is also studied. Then, the inflation process is verified by numerical simulation with C-9 parachute, key performance parameters, such as projected area, full inflation distance and canopy deformation during inflation, are compared with test results. For testing and verifying further dependability of mathematical model and rationality of simplifying hypothetic, cone parachute is carried out example analysis. To study the Parachute service behavior in the work environment of low density, supersonic velocity and low dynamic pressure, using the disk-gap-band, nominal diameter 12.2 meters as object of study, the paper carries through numerical simulation for parachute opening process in the two different altitudinal test. Parachute opening performance in the high altitude at high speed is compared with one in low altitude at low speed. Finally, simulations for parachute opening process of Mars Pathfinder parachute in the Mars and Earth atmospheric environment have been carried out.In the paper, canopy deformation and corresponding fluid field variation around canopy carried through specialization study in order to analyze the parachute entire opening process intuitively and obtain the load-carrying capacity in the different points, and provide theory criterion for the optimization design of parachute.