Mixed explicit/implicit time integration of coupled aeroelastic problems: Three‐field formulation, geometric conservation and distributed solution

Abstract

SUMMARYA three-field arbitrary Lagrangian-Eulerian (ALE) finite element/volume formulation for coupled transient aeroelastic problems is presented. The description includes a rigorous derivation of a geometric conservation law for flow problems with moving boundaries and unstructured deformable meshes. The solution of the coupled governing equations with a mixed explicit (fluid)/implicit (structure) staggered procedure is discussed with particular reference to accuracy, stability, distributed computing, I/O transfers, subcycling and parallel processing. A general and flexible framework for implementing partitioned solution procedures for coupled aeroelastic problems on heterogeneous andor parallel computational platforms is described. This framework and the explicit/ implicit partitioned procedures are demonstrated with the numerical investigation on an iPSC-860 massively parallel processor of the instability of flat panels with infinite aspect ratio in supersonic airstreams.

A partitioned coupling approach for dynamic fluid–structure interaction with applications to biological membranes

“…The former category of non-boundary-fitting methods encompasses a range of closely related methods that originate from the immersed boundary method, pioneered by Peskin [5], whereas within the latter category of boundary-fitting methods, one of the most well-known techniques used is the arbitrary Lagrangian-Eulerian (ALE) formulation. Further distinctions between methods can be made depending on the choice of the time integration scheme employed; semi-discrete methods combining a discrete time integration scheme and spatial finite elements have been applied in [6][7][8][9], whereas finite element interpolations over both space and time domains, known as the space-time finite element method, have been applied in [10][11][12][13][14]. An important aspect of boundary-fitted methods, which makes them particularly advantageous within the modelling of the FSI problems, is the ability to capture the position of the moving fluid-structure interface very accurately.…”

Coupled adjoint‐based sensitivities in large‐displacement fluid‐structure interaction using algorithmic differentiation

“…The mesh M = M (z, u) becomes a third field of the problem, as large displacements on the structural mesh are subject to change the fluid domain. This three-field formulation was first proposed by Farhat et al [51] and was further developed by Maute and co-workers [7,8,11,52]. According to Maute et al, [11], this formulation is suitable for problems with large structural deformations, even though it has a higher computational cost than two-field approaches used by Martins et al [9,10,16].…”

Incorporation of Feedback Control into a High-Fidelity Aeroservoelastic Fighter Aircraft Model

“…The three-field arbitrary Lagrangian-Eulerian (ALE) can be used to represent the nonlinear aeroelastic system [22]. Semidiscretization by a finite volume method produces three coupled ordinary differential systems of equations [Eq.…”