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The OpenFOAM Turbomachinery The OpenFOAM Turbomachinery Working Group, and Conclusions Working Group, and Conclusions
from the Turbomachinery Session of from the Turbomachinery Session of the Third OpenFOAM Workshopthe Third OpenFOAM Workshop
Maryse Page and Martin BeaudoinHydro-Québec, Research Institute
24th IAHR SymposiumOctober 27-31, 2008, Foz do Iguasso
Håkan NilssonChalmers University of
Technology, SVC
Bernhard GschaiderICE Strömungsforschung
Hrvoje JasakWikki Ltd.
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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OutlineOutline
OpenFOAM CFD toolbox
OpenFOAM Turbomachinery Working Group Objectives and contributions
Third OpenFOAM Workshop in Milano, June 2008:– Code
– Validation: ERCOFTAC conical diffuser
– Technical presentations
Next meeting: Turbomachinery Workgroup day at Fourth OpenFOAM Workshop in Montréal, June 2009
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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About the OpenFOAM CFD toolboxAbout the OpenFOAM CFD toolbox
OpenFOAM: Open Field Operation and Manipulation An OpenSource object oriented C++ tool for solving PDE's
http://www.openfoam.org
OpenSource: We have insight into the code
We can make development and tailor-made solvers
We can make research implementations available and results reproducable
We can use a large number of CPUs without extra cost
Access to an international community of OpenFOAM users
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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About the OpenFOAM CFD toolboxAbout the OpenFOAM CFD toolbox
Preprocessing: Grid generators, converters and manipulators Case setup
Postprocessing: OpenSource Paraview Access to postprocessing tools (Ensight, etc) through
conversion Many specialized CFD solvers implemented, e.g.
simpleFoam: A finite volume steady-state solver for incompressible, turbulent flow of non-Newtonian fluids, using the SIMPLE algorithm
turbFoam: A finite volume solver for unsteady incompressible, turbulent flow of non-Newtonian fluids, using the PISO algorithm
icoDyMFoam: Sliding/moving grid
Runs in parallel using automatic/manual domain decomposition
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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About the OpenFOAM Turbo WG About the OpenFOAM Turbo WG
Initiated at the Second OpenFOAM Workshop in Zagreb, June 2007
Steering committee:Maryse Page, Martin Beaudoin (Hydro-Québec)and Håkan Nilsson (Chalmers)
Homepage: OpenFOAM Wiki: http://openfoamwiki.net/index.php/Sig_Turbomachinery
Code sharing: A branch of the OpenFOAM-extend project on
SourceForge.net
Contact:[email protected]
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Objectives of the Working Group Objectives of the Working Group
Identify common interests with OpenFOAM for turbomachinery, and plan joint activities
Develop OpenFOAM for turbomachinery applications, including pre-processing, solution methods, and post-processing.
Provide tutorials on how to produce accurate results using OpenFOAM in turbomachines.
Distribute relevant validation test cases and corresponding OpenFOAM applications.
Use OpenFOAM to develop Best Practice Guidelines for CFD in turbomachines.
Connect people with the same interest: OpenFOAM and turbomachinery.
Organize meetings, workshops and collaborations
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Contributions to OpenFOAM WikiContributions to OpenFOAM Wiki
Developments Descriptions of contributed solvers, utilities and libraries.
→ Source code on SourceForge.net
Tutorials How to implement (new application, boundary condition,
turbulence model)
Cylindrical coordinate systems
Validation test cases ERCOFTAC conical diffuser
Link to Turbine-99 draft tube
List of publications
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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OpenFOAM-extend on SourceForge.netOpenFOAM-extend on SourceForge.net
Contributions to Turbomachinery branch: Source codes:
– Mesh converters:
• cgnsToFoam
• foamToCGNS
– Pre-processing tools:
• addSwirlAndRotation
– Specialized BC:
• profile1DfixedValue
Case-studies/tutorials/validation:– ercoftacConicalDiffuser
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Work in progressWork in progress
Development and testing: General Grid Interfaces
Mixing plane interfaces
Filtered k-ω SST turbulence model
Cavitation modelling: VOF with mass-transfer (cavInterFoam)
Automatic parallel benchmarking for hydraulic turbines applications on large clusters
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Workshop Case study: Workshop Case study: ERCOFTAC Conical DiffuserERCOFTAC Conical Diffuser
Ref: P.D. Clausen, S.G.Koh and D.H.Wood,Measurements of a Swirling Turbulent Boundary Layer Developing in a Conical Diffuser,Experimental Thermal and Fluid Science 1993, 6:39-48
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Workshop Case study: Workshop Case study: ERCOFTAC Conical DiffuserERCOFTAC Conical Diffuser
Instructions and comments on OpenFOAM Wiki
All files available on OpenFOAM-extend cases set-up
experimental data
applications, libraries
Mesh parametrization for blockMesh using m4 (O-grid, radial grid)
Automatic post-processing (sample, gnuplot)
Documentation
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Cases in OF Wiki and OpenFOAM-extendCases in OF Wiki and OpenFOAM-extend
Case0 Case2Case1
Case1: Extended base caseCase1.1: Radial meshCase1.2: MFRSimpleFoamCase1.3: 2D wedge mesh
Case2: Case1 with a dumpCase2.1: Inlet velocity profileCase2.2: Radial mesh
Case0: Base case
• All cases except Case1.2 use simpleFoam• k-ε with wall functions, average y+: 25-27• div(phi,U) Gauss linearUpwind Gauss;• div(phi,k) Gauss upwind; • div(phi,epsilon) Gauss upwind;
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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A B C D E F
Example: Case1.2: Example: Case1.2: Case1 with MRFSimpleFoamCase1 with MRFSimpleFoam
diffuserLength extensionLength
Out
let,
D d
epen
ds o
n
openingAngle
rIn,
diff
user
Len
gth
and
open
ingA
ngle
z
Inle
t, D
= 2
*rIn
0.5mrA
rRelA * rA
rRelAc * rRelA * rA
tNumberOfCells
rNumberOfCells
Rotating part (MRF)
Cross-sections for mesh control(there are m4 parameters for axial locations and mesh density)
m4 parameters
Cross-sectionmesh topology and
m4 parameters
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Axial (U) and tangential (W) velocity atZ=25mm, Case0/1/2
Results: ERCOFTAC Conical DiffuserResults: ERCOFTAC Conical Diffuser
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
0 20 40 60 80 100 120 140 160 180 200 220
U/(
U_0
)
y (mm)
Section z = 025mm
Measured UMeasured W
Case0, UCase0, WCase1, UCase1, WCase2, UCase2, W
25 60100 175 250 330
405
Inlet-25
U
W
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Results: ERCOFTAC Conical DiffuserResults: ERCOFTAC Conical Diffuser
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
0 20 40 60 80 100 120 140 160 180 200 220
U/(
U_0
)
y (mm)
Section z = 405mm
Measured UMeasured W
Case0, UCase0, WCase1, UCase1, WCase2, UCase2, W
25 60100 175 250 330
405
Inlet-25
Axial (U) and tangential (W) velocity atZ=405mm, Case0/1/2
U
W
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Results: ERCOFTAC Conical DiffuserResults: ERCOFTAC Conical Diffuser
0
0.0025
0.005
0.0075
0.01
0.0125
0.015
0 20 40 60 80 100 120 140 160 180 200 220
k/(U
_0^2
)
y (mm)
Section z = 025mm
Measured kCase0, kCase1, kCase2, k
25 60100 175 250 330
405
Inlet-25
Turbulent kinetic energy (k) atZ=25mm, Case0/1/2
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Results: ERCOFTAC Conical DiffuserResults: ERCOFTAC Conical Diffuser
0
0.0025
0.005
0.0075
0.01
0.0125
0.015
0 20 40 60 80 100 120 140 160 180 200 220
k/(U
_0^2
)
y (mm)
Section z = 405mm
Measured kCase0, kCase1, kCase2, k
25 60100 175 250 330
405
Inlet-25
Turbulent kinetic energy (k) atZ=405mm, Case0/1/2
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Tech. Presentations in Turbo SessionTech. Presentations in Turbo Session
Third OpenFOAM Workshop in Milano, June 2008: Development of a GGI interface (Beaudoin & Jasak)
LES for swirling flow in pipes (Duprat & Métais)
Turbo-gas engines: GGI, Steady compressible flow, Conjugate Heat Transfer, Boundary Conditions, Mixing Plane (Mangani & Bianchini)
Mixing Plane Interface (Blaim, Borm, Fröbel, Kau)
24th IAHR Symposium, 2008October 27-31, Foz do Iguassu
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Fourth OpenFOAM WorkshopFourth OpenFOAM Workshop
Montréal, Canada, June 1-4, 2009→ More info: http://www.openfoamworkshop.org
Turbomachinery Session
OpenFOAM Turbomachinery Workgroup Day
Next case study: ERCOFTAC centrifugal pump
M. Ubaldi, P. Zunino, et al., An Experimental Investigation of Stator Induced Unsteadiness on Centrifugal Impeller Outflow, ASME Journal of Turbomachinery, 1996.