Fluid-structure interactions of a parachute crossing the far wake of an aircraft

In this paper we describe a computational technique for simulation of the fluid-structure interactions of a parachute crossing the far wake of an aircraft. This technique relies on using the long-wake flow data already computed, in our case, with the Multi-Domain Method (MDM) we developed earlier. The fluid-structure interaction computations are carried out over a domain enclosing the parachute and moving with the payload. This domain functions as one of the subdomains of the MDM designed specifically for the parachute fluid-structure interactions considered here. The boundary conditions for this subdomain are extracted from the long-wake flow data, at locations corresponding to the positions of those boundaries in the subdomain over which the wake flow data were computed. The Navier-Stokes equations of incompressible flows, governing the fluid dynamics, are solved with the Deforming-Spatial-Domain/Stabilized Space-Time (DSD/SST) formulation, which can handle changes in the spatial domain occupied by the fluid. This formulation is coupled to the finite element formulation used for solving the membrane equations governing the structural mechanics of the parachute canopy and the equations governing the mechanics of the suspension lines. The numerical example included demonstrates how the technique described here, functioning as a component of the MDM, enables us to simulate the fluid-structure interactions of a parachute crossing an aircraft wake. (C) 2001 Elsevier Science B.V. All rights reserved.