LES/DNS fluid-structure interaction simulation of non-linear slender structures in <i> Nektar++ </i> framework
OA Location
Author(s)
Lahooti, Mohsen
Bao, Yan
Scott, David
Palacios, Rafael
Sherwin, Spencer J
Type
Journal Article
Abstract
Nektar++ is a spectral/hp element open-source framework written in C++ for the construction of classical low-order h-type as well as higher-order p-type finite element solvers. It seeks to overcome the implementation challenges of the complex data structures associated with high-order finite element methods; hence, providing an efficient, flexible and HPC scalable platform for the development of solvers for partial differential equations using the spectral/hp element method. In the present work, capabilities of Nektar++ is leveraged for development of two fluid-structure interaction (FSI) solvers for simulations of highly deformable nonlinear slender structures. The FSI solver uses the incompressible Navier-Stokes (NS) solvers of Nektar++ for fluid flow while the structural dynamics is modelled using Geometrically-Exact Composite Beams (GECB). The open-source SHARPy framework is linked to Nektar++ and used for structural simulation. Aiming at high-fidelity (LES/DNS) FSI simulations, the thick-strip approach is used to reduce computational costs. In this approach, the full 3D fluid domain is represented with series of smaller 3D domains normal to the local axis of the structure and having a finite thickness in the spanwise direction where periodicity is also assumed. Hence, while reducing the computational costs by avoiding the discretization of equations over the entire slender structure, the strip thickness allows capturing the local 3D turbulent wake and accurately predict the fluid forces on the structure. Two approaches are adopted to avoid the dynamic remeshing due to the large and non-linear deformation of the structure. In the first approach, the transformed the NS equations are solved in the non-inertial body-fitted coordinates while in the second approach the NS equations are formulated in the moving frame of reference and solved with the spectral/hp element method. A hybrid parallelisation approach of Nektar++ is extended for the thick-strip method which allows having non-constant cross-section along the structural span as well as efficient and flexible use of computational resources, and excellent HPC performance for the FSI simulations. The capability of the FSI solver is demonstrated via several examples.
Date Issued
2023-01-01
Date Acceptance
2022-09-04
Citation
Computer Physics Communications, 2023, 282
ISSN
0010-4655
Publisher
Elsevier
Journal / Book Title
Computer Physics Communications
Volume
282
Copyright Statement
© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license
License URL
Identifier
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000864556500004&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=a2bf6146997ec60c407a63945d4e92bb
Subjects
ACCURATE
Computer Science
Computer Science, Interdisciplinary Applications
Direct numerical simulation
DIRECT NUMERICAL SIMULATIONS
ELEMENT METHODS
FLOW
Fluid structure interaction
Geometrically-exact composite beam
Large Eddy simulation
NAVIER-STOKES EQUATIONS
Nektar plus plus
Physical Sciences
Physics
Physics, Mathematical
PREDICTION
RISER
ROBUST
Science & Technology
SHARPy
SPECTRAL VANISHING VISCOSITY
Technology
Vortex induced vibration
WINGS
Publication Status
Published
Article Number
ARTN 108528
Date Publish Online
2022-09-08