Validation of a new fluid—structure interaction framework for non-linear instabilities of 3D aerodynamic configurations

In this paper, the flow over pitching and heaving hydrofoil is investigated. The viscous incompressible Navier-Stokes problem in Arbitrary Lagrangian-Eulerian (ALE) formulation is solved using the finite elements code Cast3M. The projection method is used to uncouple the velocity and pressure fields. The implicit Euler scheme is applied for time discretization of fluid equations. The dynamics of the hydrofoil is governed by a non-linear ordinary differential equation. The non-linear coupled problem is solved using the explicit staggered algorithm. The effects of fluid-structure interaction on hydrofoil dynamics and pressure center position are analyzed.

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Numerical investigation of flexible flapping wings using computational fluid dynamics/computational structural dynamics method

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410016671343 ◽

2016 ◽

Vol 232 (1) ◽

pp. 85-95 ◽

Cited By ~ 4

Author(s):

Long Liu ◽

Hongda Li ◽

Haisong Ang ◽

Tianhang Xiao

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Structural Dynamics ◽

Fluid Structure Interaction ◽

Flapping Wings ◽

Structural Dynamic ◽

Fluid Structure ◽

Structure Interaction ◽

Non Linear ◽

Computational Structural Dynamics

A fluid–structure interaction numerical simulation was performed to investigate the flow field around a flexible flapping wing using an in-house developed computational fluid dynamics/computational structural dynamics solver. The three-dimensional (3D) fluid–structure interaction of the flapping locomotion was predicted by loosely coupling preconditioned Navier–Stokes solutions and non-linear co-rotational structural solutions. The computational structural dynamic solver was specifically developed for highly flexible flapping wings by considering large geometric non-linear characteristics. The high fidelity of the developed methodology was validated by benchmark tests. Then, an analysis of flexible flapping wings was carried out with a specific focus on the unsteady aerodynamic mechanisms and effects of flexion on flexible flapping wings. Results demonstrate that the flexion will introduce different flow fields, and thus vary thrust generation and pressure distribution significantly. In the meanwhile, relationship between flapping frequency and flexion plays an important role on efficiency. Therefore, appropriate combination of frequency and flexion of flexible flapping wings provides higher efficiency. This study may give instruction for further design of flexible flapping wings.

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Numerical Validation of the Two-Way Fluid-Structure Interaction Method for Non-Linear Structural Analysis under Fire Conditions

Journal of Marine Science and Engineering ◽

10.3390/jmse9040400 ◽

2021 ◽

Vol 9 (4) ◽

pp. 400

Author(s):

Donghan Woo ◽

Jung Kwan Seo

Keyword(s):

Structural Analysis ◽

Oil Spills ◽

Proper Time ◽

Fluid Structure Interaction ◽

Structural Response ◽

Offshore Structures ◽

Fire Dynamics ◽

Fluid Structure ◽

Structure Interaction ◽

Non Linear

Fire accidents on ships and offshore structures lead to complex non-linear material and geometric behavior, which can cause structural collapse. This not only results in significant casualties, but also environmental catastrophes such as oil spills. Thus, for the fire safety design of structures, precise prediction of the structural response to fire using numerical and/or experimental methods is essential. This study aimed to validate the two-way fluid-structure interaction (FSI) method for predicting the non-linear structural response of H-beams to a propane burner fire by comparison with experimental results. To determine the interaction between a fire simulation and structural analysis, the Fire-Thermomechanical Interface model was introduced. The Fire Dynamics Simulator and ANSYS Parametric Design Language were used for computational fluid dynamics and the finite element method, respectively. This study validated the two-way FSI method for precisely predicting the non-linear structural response of H-beams to a propane burner fire and proposed the proper time increment for two-way FSI analysis.

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Identification of Non-Linear Damping of Nuclear Reactor Components in Case of One-to-One Internal Resonance

Volume 4A: Dynamics, Vibration, and Control ◽

10.1115/imece2016-66311 ◽

2016 ◽

Cited By ~ 3

Author(s):

Joachim Delannoy ◽

Marco Amabili ◽

Brett Matthews ◽

Brian Painter ◽

Kostas Karazis

Keyword(s):

Fuel Assembly ◽

Internal Resonance ◽

Fluid Structure Interaction ◽

Fundamental Parameter ◽

Pressurized Water ◽

Fluid Structure ◽

Structure Interaction ◽

Safety Margins ◽

Non Linear ◽

One To One

In Pressurized Water Reactors (PWR) assemblies are exposed to challenging thermal, mechanical, and irradiation loads during operation. Global core and local fuel assembly flow fields coupled with seismic excitation result in fuel assembly and fuel rod vibrations. The fact that vibrations may become excessive in certain conditions has consequences on operational safety margins in fuel assemblies designs. In order to understand how the fuel assembly responds dynamically to an external excitation, it is important to identify the main characteristics of the structures. Among them, the fuel assembly system damping is a fundamental parameter that is usually identified by a number of experiments involving fluid-structure interaction. Recent studies have shown that the damping ratio increases with the excitation force when the structure is entering large-amplitude vibrations, in which case the geometric non-linearities have to be taken into account. The present paper presents an advanced identification procedure developed to identify the system characteristics from experimental non-linear response curves obtained from forced vibration tests, accounting for fluid-structure interaction, at different excitation levels. Furthermore, the numerical tool developed in this analysis is capable of working with systems presenting one-to-one internal resonance, i.e. systems with symmetry such as circular tubes and circular cylindrical shells. The method relies on a harmonic decomposition of the displacement to cope with the data usually available by vibration measurements.

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Finite Element Approximation of Fluid Structure Interaction (FSI) Optimization in Arbitrary Lagrangian-Eulerian Coordinates

Volume 7B: Fluids Engineering Systems and Technologies ◽

10.1115/imece2013-62291 ◽

2013 ◽

Cited By ~ 1

Author(s):

Bhuiyan Shameem Mahmood Ebna Hai ◽

Markus Bause

Keyword(s):

Finite Element ◽

Fluid Structure Interaction ◽

Arbitrary Lagrangian Eulerian ◽

Fluid Structure ◽

Structure Interaction ◽

Finite Element Software ◽

Special Cases ◽

Non Linear ◽

Non Linear System ◽

The Impact

Advanced composite materials such as Carbon Fiber Reinforced Plastics (CFRP) are being applied to many aircraft structures in order to improve performance and reduce weight. Most composites have strong, stiff fibers in a matrix which is weaker and less stiff. However, aircraft wings can break due to Fluid-Structure Interaction (FSI) oscillations or material fatigue. This paper focuses on the analysis of a non-linear fluid-structure interaction problem and its solution in the finite element software package DOpElib: the deal.II based optimization library. The principal aim of this research is to explore and understand the behaviour of the fluid-structure interaction during the impact of a deformable material (e.g. an aircraft wing) on air. Here we briefly describe the analysis of incompressible Navier-Stokes and Elastodynamic equations in the arbitrary Lagrangian-Eulerian (ALE) frameworks in order to numerically simulate the FSI effect on a double wedge airfoil. Since analytical solutions are only available in special cases, the equation needs to be solved by numerical methods. This coupled problem is defined in a monolithic framework and fractional-step-θ time stepping scheme are implemented. Spatial discretization is based on a Galerkin finite element scheme. The non-linear system is solved by a Newton method. The implementation using the software library package DOpElib and deal.II serves for the computation of different fluid-structure configurations.

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Adaptive reduced-order modeling for non-linear fluid-structure interaction

Computers & Fluids ◽

10.1016/j.compfluid.2021.105099 ◽

2021 ◽

pp. 105099

Author(s):

Ali Thari ◽

Vito Pasquariello ◽

Niels Aage ◽

Stefan Hickel

Keyword(s):

Fluid Structure Interaction ◽

Reduced Order Modeling ◽

Fluid Structure ◽

Reduced Order ◽

Structure Interaction ◽

Non Linear

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The Comparison of Different Constitutive Laws and Fiber Architectures for the Aortic Valve on Fluid–Structure Interaction Simulation

Frontiers in Physiology ◽

10.3389/fphys.2021.682893 ◽

2021 ◽

Vol 12 ◽

Author(s):

Li Cai ◽

Ruihang Zhang ◽

Yiqiang Li ◽

Guangyu Zhu ◽

Xingshuang Ma ◽

...

Keyword(s):

Aortic Valve ◽

Fluid Structure Interaction ◽

Constitutive Laws ◽

Constitutive Law ◽

Mechanical Behaviors ◽

Windkessel Model ◽

Fluid Structure ◽

Structure Interaction ◽

Non Linear ◽

Constitutive Parameters

Built on the hybrid immersed boundary/finite element (IB/FE) method, fluid–structure interaction (FSI) simulations of aortic valve (AV) dynamics are performed with three different constitutive laws and two different fiber architectures for the AV leaflets. An idealized AV model is used and mounted in a straight tube, and a three-element Windkessel model is further attached to the aorta. After obtaining ex vivo biaxial tensile testing of porcine AV leaflets, we first determine the constitutive parameters of the selected three constitutive laws by matching the analytical stretch–stress relations derived from constitutive laws to the experimentally measured data. Both the average error and relevant R-squared value reveal that the anisotropic non-linear constitutive law with exponential terms for both the fiber and cross-fiber directions could be more suitable for characterizing the mechanical behaviors of the AV leaflets. We then thoroughly compare the simulation results from both structural mechanics and hemodynamics. Compared to the other two constitutive laws, the anisotropic non-linear constitutive law with exponential terms for both the fiber and cross-fiber directions shows the larger leaflet displacements at the opened state, the largest forward jet flow, the smaller regurgitant flow. We further analyze hemodynamic parameters of the six different cases, including the regurgitant fraction, the mean transvalvular pressure gradient, the effective orifice area, and the energy loss of the left ventricle. We find that the fiber architecture with body-fitted orientation shows better dynamic behaviors in the leaflets, especially with the constitutive law using exponential terms for both the fiber and cross-fiber directions. In conclusion, both constitutive laws and fiber architectures can affect AV dynamics. Our results further suggest that the strain energy function with exponential terms for both the fiber and cross-fiber directions could be more suitable for describing the AV leaflet mechanical behaviors. Future experimental studies are needed to identify competent constitutive laws for the AV leaflets and their associated fiber orientations with controlled experiments. Although limitations exist in the present AV model, our results provide important information for selecting appropriate constitutive laws and fiber architectures when modeling AV dynamics.

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