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
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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