Fluid-Structure Interaction (FSI) and CFD Analysis Package in Abaqus

Fluid-Structure Interaction (FSI) and CFD Analysis in Abaqus

Introduction to Fluid-Structure Interaction (FSI)

Fluid-Structure Interaction (FSI) is a multiphysics phenomenon where a fluid and a solid structure interact, leading to deformation in the structure and changes in the fluid flow. FSI problems are common in engineering applications such as

Aerodynamics (aircraft wings, wind turbines)

Biomedical engineering (blood flow in arteries, heart valves)

Civil engineering (bridge flutter, offshore structures)

Automotive engineering (car aerodynamics, fuel tanks)

Types of FSI Problems

One-way FSI: Fluid forces affect the structure, but structural deformations do not influence the fluid flow (e.g., static pressure loads)

Two-way FSI: Fluid and structure mutually influence each other (e.g., flutter, sloshing, flexible pipes)

Computational Fluid Dynamics (CFD) in Abaqus

Abaqus is primarily a Finite Element Analysis (FEA) software, but can perform CFD simulations using

Abaqus/CFD (standalone module for fluid flow)

Co-simulation with Abaqus/Standard or Abaqus/Explicit (for coupled FSI problems)

Key Features of Abaqus/CFD

Solves Navier-Stokes equations for incompressible/weakly compressible flows, Supports laminar and turbulent flows (k-ε, k-ω models), Mesh motion techniques (ALE – Arbitrary Lagrangian-Eulerian), Coupling with structural solvers for FSI

Coupling Methods in Abaqus

Co-Simulation (Two-way FSI)

Abaqus/CFD (fluid solver) + Abaqus/Standard or Explicit (structural solver)

Data exchange at each time step (pressure/forces → structure, displacements → fluid mesh)

One-way Coupling

Export CFD pressure loads and apply them as static loads in a structural analysis

Challenges in FSI Simulations

Mesh Compatibility: Fluid and structure meshes must align at the interface

Numerical Instability: Large deformations may require remeshing or ALE techniques

Computational Cost: High-resolution CFD + structural coupling increases solve time

Convergence Issues: Strong coupling requires sub-iterations for stability

Best Practices for FSI in Abaqus

Start with simplified models before full-scale simulations

Use coarse meshes initially for debugging

Validate with analytical solutions or experiments

Monitor energy balance to ensure stability

Consider parallel computing for faster solutions

Conclusion

FSI is a critical multiphysics problem requiring coupled CFD and structural analysis

Abaqus provides tools for co-simulation and one-way coupling

Challenges include mesh handling, convergence, and computational cost

Proper modeling techniques can simulate real-world FSI problems effectively

In this package, you will learn all types of FSI and CFD Modeling and Simulation, including all materials and methods 

The package contains fourteen separate tutorials, including cae, inp, code, paper, reference of the materials, and a step-by-step English video. You can check the titles of the tutorials below