fluid-structure interaction of thin structures in

Fluid-Structure Interaction of Thin Structuresin Turbulent Flows

G. De Nayer, A. Kalmbach and M. Breuer

Department of Fluid Mechanics (PfS)

Helmut–Schmidt–University (HSU), Hamburg, Germany

M. Munsch S. Sicklinger, R. Wuchner, K.U. BletzingerInstitute of Fluid Mechanics Chair of Structural Analysis

University of Erlangen–Nurnberg, Germany Technical University of Munich, Germany

SuperMUC Review WorkshopGarching, July 2014 SfP

1 Motivation / Objectives

2 Computational Methodology

3 ValidationDefinition of the Test CasesSimulations and Comparison with Experiments (FSI-PfS-2a)

4 Conclusions

Outline 2




4 Conclusions

Outline 3

Tents / Sun Shades /Mobile Umbrellas

Motivation / Long-term Objectives 4




4 Conclusions

Outline 5

FSI in Turbulent Flows

CFD CSD

p, FτF

PartitionedApproach

∆ x

Publication

Breuer, M., De Nayer, G., Munsch, M., Gallinger, T., Wuchner, R.:

Fluid-Structure Interaction Using a Partitioned Semi-Implicit Predictor-CorrectorCoupling Scheme for the Application of Large-Eddy Simulation.

Journal of Fluids and Structures 29, 107-130, 2012.

Computational Methodology:FSI with LES and Thin Structures

6

Momentum Eq.

Runge−Kutta

Poisson Eq.

u*

u , p

Pre

dic

tor

Co

rre

cto

r

Block−struct. grids

i

i

FASTEST−3D

FVM (2 order)

Predict.−Correct.

LES

ALE

nd


7

Forceson the

Estimationof structural

displacements

Momentum Eq.Runge−Kutta

Poisson Eq.

structure

Grid

u*

u , p

Pre

dict

orC

orre

ctor

Predict.−Correct.

nd

i

i

adaptation

FASTEST−3DFVM (2 order)

LES

ALE



7

Forces

on the


displacements

Momentum Eq.

Runge−Kutta

Poisson Eq.

structure

step

Grid

Next time

u*

u , p

Pre

dic

tor

Co

rre

cto

r


Predict.−Correct.

nd

i

i

adaptation

yes

no

FASTEST−3D

FVM (2 order)

Carat++

FEM

Generalized

α −method

Membranes

Shells

Index: n

LES

ALE

Partitioned

Approach

Grid

adaptation


7

Forces

on the


displacements

Momentum Eq.

Runge−Kutta

Poisson Eq.

structure

step

Grid

Next time

?

u*

u , p

Pre

dic

tor

Co

rre

cto

r


Predict.−Correct.

nd

i

i

adaptation

FSI convergence

yes

no

FSI−Subiteration Loop

(conservative)

FASTEST−3D

FVM (2 order)

CoMA MPI

Interpolation

Grid−to−GridFluid Force

Grid−to−Grid

(ensure dynamic equilibrium)

Displacement

Interpolation(bilinear)

DisplacementsUnderrelax. of

Carat++

FEM

Generalized

α −method

Membranes

Shells

Index: n

Index: k

LES

ALE

Partitioned

Approach

Grid

adaptation


7




4 Conclusions

Outline 8




4 Conclusions

Outline 9

FSI-PfS-1a

EPDM−rubber

fixed cylinder

60 m

m

2 mm

22 mm

(flexible)

(rigid)

E = 16 MPa= 0.48

u∞Ø

ν

– Re = 30,470– quasi 2D-deformations– small deformations– first swiveling mode

FSI-PfS-2a

2 mm

fixed cylinder

10 m

m

para−rubber

50 m

m

22 mm

steel (rigid)

(flexible)

(rigid)

E = 4.10 MPa

= 0.48

u∞Ø

ν

– Re = 30,470– 2D-deformations– large deformations– second swiveling mode

FSI Test Cases for Turbulent Flows 10

Publications for FSI-PfS-1a

De Nayer, G., Kalmbach, A. Breuer, M., Sicklinger, S. and Wuchner, R.:

Flow past a cylinder with a flexible splitter plate: a complementaryexperimental-numerical investigation and a new FSI test case (FSI-PfS-1a).

Int. Journal of Computers and Fluids 99, 18-43, 2014.

http://qnet-ercoftac.cfms.org.uk/w/index.php/UFR_2-13

Publications for FSI-PfS-2a

Kalmbach, A. and Breuer, M.:

Experimental PIV/V3V Measurements of Vortex-Induced Fluid-StructureInteraction in Turbulent Flow New Benchmark FSI-PfS-2a.

Journal of Fluids and Structures 42, 369-387, 2013.

De Nayer, G. and Breuer, M.:

Numerical FSI Investigation based on LES: Flow past a cylinder with a flexiblesplitter plate involving large deformations (FSI-PfS-2a).

Submitted.


FSI Test Cases for Turbulent Flows 11






4 Conclusions

Outline 12

Axial pump with motor

Flow straightener

Test section Water Channel

+Flow measurement methods (PIV / V3V)

Laser displacement sensor

⇓Experimental Data

High-speed video

(real frequency 11.25 Hz)

FSI-PfS-2a: Experiments 13

g

inflow

subset of the channel

Fluid/CFD:

• wall–resolved LES

• 13.5 million CVs

• 72 CVs in spanwise direction

• periodic boundary conditions

Structure/CSD:

• 7–parameter shell elements

• 30 × 10 quadrilateralfour-node elements

• zero z–deformation vs.periodic b.c.

• (Rayleigh damping)

FSI-PfS-2a: Computational Setup 14

93 cores needed for each simulation13.5 million CVs on 91 blocks → 91 processes for CFD

1 process for CSD

1 process for coupling program

2 seconds physical time computed for each simulation

CPU: 1000 hours wall-clock

RAM: 242 Mbytes per core → 22 Gbytes for the entire simulation

Sensitivity study on FSI-PfS-2a

about 30 simulations with different parameters conducted

FSI-PfS-2a: Computations on SuperMUC 15

t u / D

Uy

/D

800 850 9000.8

0.6

0.4

0.2

0

0.2

0.4

0.6

0.8

OO

EXP: Raw Signal

t u / D

Uy

/D

20 40 60 80 100 1200.8

0.6

0.4

0.2

0

0.2

0.4

0.6

0.8

OO

CFD: Raw Signal

2mm

Monitoring Point(mid plane)

FSI-PfS-2a: Deflection of the Structure 16

t u / D

Uy

/D

800 850 9000.8

0.6

0.4

0.2

0

0.2

0.4

0.6

0.8

OO

EXP: Raw Signal

t u / D

Uy

/D

20 40 60 80 100 1200.8

0.6

0.4

0.2

0

0.2

0.4

0.6

0.8

OO

CFD: Raw Signal

Phase

Uy

/D

0 2 4 60.8

0.6

0.4

0.2

0

0.2

0.4

0.6

0.8NumExp

AveragedPhase

FSI-PfS-2a: Deflection of the Structure 16

Frequency

St fFSI Error

(Hz) (%)

EXP 0.177 11.25 -

CFD 0.183 11.53 2.49

FSI-PfS-2a: Comparison Experiment/Simulation 17

Frequency

St fFSI Error

(Hz) (%)

EXP 0.177 11.25 -

CFD 0.183 11.53 2.49

Displacements

Uy/D|max Error Uy/D|min Error

(%) (%)

EXP 0.667 - -0.629 -

CFD 0.670 0.5 -0.674 7.2

FSI-PfS-2a: Comparison Experiment/Simulation 17

Streamwise velocity in the midplane

FSI-PfS-2a: Simulated Instantaneous Flow 18

Streamwise velocity Transverse velocity

EXP

CFD

FSI-PfS-2a: Comparison of Phase-averaged Data(t ≈ 1/24 T)

19

Streamwise velocity Transverse velocity

EXP

CFD

FSI-PfS-2a: Comparison of Phase-averaged Data(t ≈ 5/24 T)

20




4 Conclusions

Outline 21

Computational Methodology for FSI and ThinStructures

Each program specialized in its task

Each program parallelized (MPI, OpenMP)

New FSI coupling scheme developed

+ based on explicit time–marching scheme (predictor–corrector),but nevertheless stable and strong FSI algorithm

+ corrector step and structural computation directly connected ina FSI subiteration loop to achieve dynamic equilibrium

Conclusions 22

Computational Methodology for FSI and ThinStructures

Each program specialized in its task

Each program parallelized (MPI, OpenMP)

New FSI coupling scheme developed

+ based on explicit time–marching scheme (predictor–corrector),but nevertheless stable and strong FSI algorithm

+ corrector step and structural computation directly connected ina FSI subiteration loop to achieve dynamic equilibrium

Validation

Methodology validated for laminar flows (not presented here)

Methodology validated for turbulent flows (FSI-PfS-2a,...)

Generation of FSI test cases for the community with experimentaland numerical data available online (ERCOFTAC/QNET wiki)

Conclusions 22

Outlook

New coupling program (EMPIRE) → more flexibility in thecoupling

Reduce the CPU costs with the help of special wall models

Acknowledgments:

- Thanks to Jens Nikolas Wood for his support.

- Financially supported by the Deutsche Forschungsgemeinschaft (BR 1847/12-1)

- Computations on the Top-Level Computer SuperMUC at LRZ Munich.

Outlook 23

Thanks for your attention 24

fluid-structure interaction of thin structures in

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