A high-order in space spectral-element methodology for the solution of a strongly coupled fluid-structure interaction (FSI) problem is developed. A methodology is based on a partitioned solution of incompressible fluid equations on body-fitted grids, and nonlinearly-elastic solid deformation equations coupled via a fixed-point iteration approach with Aitken relaxation. A comprehensive verification strategy of the developed methodology is presented, including h-, p-and temporal refinement studies. An expected order of convergence is demonstrated first separately for the corresponding fluid and solid solvers, followed by a self-convergence study on a coupled FSI problem (self-convergence refers to a convergence to a reference solution obtained with the same solver at higher resolution). To this end, a new three-dimensional fluid-structure interaction benchmark is proposed for a verification of the FSI codes, which consists of a fluid flow in a channel with one rigid and one flexible wall. It is shown that, due to a consistent problem formulation, including initial and boundary conditions, a high-order spatial convergence on a fully coupled FSI problem can be demonstrated. Finally, a developed framework is applied successfully to a Direct Numerical Simulation of a turbulent flow in a channel interacting with a compliant wall, where the fluid-structure interface is fully resolved.
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IGA-PD penalty-based coupling for immersed air-blast fluid–structure interaction: a simple and effective solution for fracture and fragmentation
We present a novel formulation for the immersed coupling of isogeometric analysis and peridynamics for the simulation of fluid–structure interaction (FSI). We focus on air-blast FSI and address the computational challenges of immersed FSI methods in the simulation of fracture and fragmentation by developing a weakly volume-coupled FSI formulation by means of a simple penalty approach. We show the mathematical formulation and present several numerical examples of inelastic ductile and brittle solids under blast loading that clearly demonstrate the power and robustness of the proposed methodology.
more » « less- NSF-PAR ID:
- 10361077
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Mechanics
- Volume:
- 37
- ISSN:
- 1811-8216
- Page Range / eLocation ID:
- p. 680-692
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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