Fluid-Structure Interaction using

STAR-CCM+ and Abaqus Co-Simulation

Alan Mueller

The Challenges of FSI

Mapping data techniques

– Finding neighbors and interpolating

Protocols and formats for exchanging data

– Getting data from Code A to Code B

Coupling methods

– Algorithms for accuracy, stability

Dynamic fluid mesh evolution

– Topology changes in the fluid domain

Validation of FSI results

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Abaqus/STAR-CCM+ Co-Simulation

Coupling via Abaqus Co-Simulation API of SIMULIA – Manages Coupling Synchronization/Exchange/Mapping

– Abaqus v6.11/STAR-CCM+ v6.06

– Abaqus v6.12/STAR-CCM+ v7.04 (implicit coupling)

Surface to Surface Mapping

– STAR-CCM+ Abaqus (explicit or standard) • Initial geometry

• Pressure(relative or absolute pressure)

• Shear traction

• Surface heat flux

– Abaqus STAR-CCM+ • Displacement, velocity

• Temperature

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Abaqus/STAR-CCM+ Co-Simulation Interface

Hit the Step or Run

button to commence the

co-simulation

Benchmark: VIV of Cylinder/Cantilevered Plate

FSI3 Benchmark of Turek & Hron

– heavy fluid interacting with light and compliant solid

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Loads and Displacements within 10% of

Benchmark Numerical Results

Co-Simulation: Plate Vortex Induced Vibration

Elastic plate perpendicular to air stream

– 10 cm x 8 cm x 2.5mm

– density and modulus such that

• 1st bending mode @ 4Hz

• 1st twisting mode @ 20 Hz

Compressible air moving at 10 m/s, Re=5e4

– K- turbulence model, Unsteady RANS

– Rigid plate, computed Cd=2.0, Str=0.156

• Vortex shedding frequency @ 19.5 Hz

• Produces very small twisting moment

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Long Term VIV Response

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Only twisting mode is not completely damped!

Experimental Validation: Wedge Drop In Water

Comparison of Experiments and Models

Peterson, Wyman, and Frank: “Drop Tests to Support

Water-Impact and Planing Boat Dynamics Theory”,

Dahlgren Division Naval Surface Warfare Center,

CSS/TR-97/25

STAR-CCM+ VOF with different bodies

– Rigid Body (6DOF, DFBI)

– Elastic Body (FV stress)

– Elastic Body (Abaqus Co-Simulation)

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Wedge Drop In Water: VOF and Mises Stress

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Wedge Drop In Water

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Vertical acceleration (m/s2) Angular acceleration (rad/s2)

All Methods give good agreement to experiments

6DOF + FEA of Tanker and Offshore Platform

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Wind Turbine Under Steady Wind

Windward Displacement

Blade deformation negatively impacts efficiency: trade-off on

costs for stiff blades versus less efficient power generation

AeroElastic Prediction Workshop: HIRANASD

Fluid and Structural Models for FSI Simulations

Aerodynamic Equilibrium Wing at different AOA

Static Structure, Steady airflow at deformed shape

Ma=0.8, Re=23.5x106, q/E=0.48x10-6

Wing Tip Displacement Lift Coefficient

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q/E = 0.48e-6; M = 0.8; Re = 23.5e6

HIRANASD: AEC Lift, Drag and Cp

FUN3D STAR-CCM+/Abaqus

HIRANASD Forced Wind-on Vibration

Quantity CCM+ SOFIA Error,% Exp.#270 Error,%

f, Hz 29.54 29.50 0.1% 29.10 1.5%

-Cp' / acc15/1 1.79E-04 1.99E-04 -9.9% 2.23E-04 -19.6%

STAR-CCM+/Abaqus Sofia

Change in Cp relative to the tip acceleration

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Co-Simulation DOT Tank Impact

Experimental Test Facility

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DOT Tank Impact Simulations

Von Mises Stress (Abaqus Explicit) STAR-CCM+ Pressure

• STAR-CCM+ :14 cores, Abaqus Explicit: 1 core

• Elapsed Time 48 Hours

DOT Tank Impact Comparisons

0

200

400

600

800

1000

1200

1400

Star-CD/Abaqus

Direct Coupling

Time (seconds)

Imp

act F

orc

e (

kip

s)

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Thank You For Your Attention & Enjoy