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NASA NTRS · 20190030858

A Higher-Order Space-Time Finite-Element Method for Moving-Body and Fluid-Structure Interaction Problems

Diosady, L.·Murman, S.·Carton de Wiart, C.
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Abstract

We present a high-order finite-element method for moving body and fluid/structure interaction problems. Our solution strategy is based on a space-time discontinuous Galerkin (DG) spectral-element discretization which extends to arbitrary order of accuracy. The space-time DG discretization is a natural choice for moving body and fluid-structure interaction problems as moving surfaces are incorporated simply by considering curved space-time elements whose space-time faces align with the moving body. We present a discontinuous-Galerkin in time discretization for six-degree of motion modeling of rigid bodies, and a continuous-Galerkin discretization for equations of linear elasticity to generate curved space-time meshes. Numerical results for several simple 2D test cases are presented in order to verify the implementation of the different models. Finally we present a preliminary dynamic simulation of a parachute.

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High-OrderFluid-StructureNumerical AlgorithmsMoving-BodySpace-TimeComputational Fluid Dynamics

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Diosady, L., Murman, S., Carton de Wiart, C.. 2018-07-09. A Higher-Order Space-Time Finite-Element Method for Moving-Body and Fluid-Structure Interaction Problems. https://ntrs.nasa.gov/citations/20190030858

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