Advanced computational methods for 3D simulation of parafoils

In this paper we provide an overview of the computational methods developed by the Team for Advanced Flow Simulation and Modeling (T*AFSM) for 3D simulation of parafoils, particularly large, ram-air parachutes. The model is based on 3D Navier-Stokes equations governing the incompressible flow around the parafoil and Newton's law of motion governing the dynamics of the parafoil, with the aerodynamic forces acting on the parafoil calculated from the flow field. The methods developed include a stabilized space-time finite element formulation that accommodates for the motion and shape changes, special mesh generation and mesh moving strategies, iterative solution techniques for the large, coupled nonlinear equation systems encountered, and parallel implementation of these methods on distributed-memory and sharedmemory parallel computing systems such as the Thinking Machines CM-5, CRAY T3E, and multiprocessor SGI systems. This set of methods developed over the past few years gives us new, powerful tools that enable us to carry out parafoil simulations at new levels of sophistication and computational scales.