A Porous Media Approach to Parachute Modeling

Modeling parachutes for atmospheric entry is challenging because of the vast number of different physical phenomena that occur during, and after the deployment. In order to do so, engineers rely on high fidelity computational fluid dynamic solvers to provide accurate predictions. Typically, the parachute is treated as a solid boundary. However, in reality, the fabric is porous, and the atmospheric gases flow can flow straight through it, especially when the fabric is fully deployed, and under aerodynamic load. The work proposed here aims at using a newly developed modeling approach to integrate the parachute fabric in the fluid dynamic simulation, and treat it as a spatially variable porous media. This new method solves the whole domain using one general set of equations for both the flow field and the porous media. This approach has the advantage of effectively removing all boundary layer assumptions currently used in parachute modeling by letting the code calculate the surface fluxes intrinsically, and not by imposing an impermeable surface, or an approximate flux balance equation. This new approach has been tested with great success on simplified geometry, and could be readily used to model parachute in steady-state. The successful completion of the project will provide a proof-of-concept validation of the approach, using experimental parachute data.