Sig Turbomachinery Feature MixingPlane Interface OpenFOAM-1.6-ext

Valid versions:

1 The mixingPlane interface for OpenFOAM-1.6-ext

1.1 Authors

• Martin Beaudoin, Hydro-Québec
• Hrv Jasak, Wikki Ltd.

1.2 Description

The mixingPlane interface is implementing the interpolation of face data between two primitivePatches using mixing plane averaging.

The mixingPlane interface is a new addition to the OpenFOAM simulation toolbox. For turbomachinery simulation, the mixingPlane is essentially a circumferential averaging interface. For steady-state simulations in hydroturbines, it is common to use a mixingPlane interface between a guide vane passage and a runner passage, or between a runner passage and a full draft tube geometry.

The main component of the mixingPlane interface is a circumferential averaging interpolator that computes and transfers average field values across the upstream and downstream patches that make up the mixingPlane. The interpolator is constructed using an intermediary cylindrical patch surface made of a stack of 360 degree ribbons shared between two specially crafted GGI interfaces.

Special care has been taken for the discretization of the cylindrical ribbon patch in order to appropriately interpolate both the coarse and fine regions of the upstream and downstream patches from the mixingPlane interface. A discretization profile is constructed based on the 2D upstream and downstream patch point distribution in cylindrical space. This 2D profile will then serve as the discretization control curve for generating the intermediary 360 degree ribbons patch. More information about the actual implementation details of the mixingPlane interface for OpenFOAM will be provided in upcoming publications.

1.3 References

   OpenFOAM TURBO TOOLS: FROM GENERAL PURPOSE CFD TO TURBOMACHINERY SIMULATIONS 
   H. Jasak, M. Beaudoin, Proceedings of ASME-JSME-KSME Joint Fluids
   Engineering Conference 2011, AJK2011-FED, July 24-29, 2011, Hamamatsu,
   Shizuoka, JAPAN 

   Steady-state capabilities for hydroturbines with OpenFOAM,
   M. Page, M. Beaudoin, A.-M. Giroux, Internationnal Journal of Fluid
   Machinery and Systems, 4(1):160–170, Jan-Mar 2011.

   Development of a General Grid Interface for Turbomachinery simulations with
   OpenFOAM, M. Beaudoin, H. Jasak, Open Source CFD International Conference,
   December 2008 

1.4 Availability

• Availability of the mixingPlane_RC1 version
• How to download
• How to compile

1.5 Current limitations

The development of the mixingPlane interface for OpenFOAM is still a work in progress at Hydro-Québec. Still, it was decided to publish a first "release candidate version" in 2012 in order to share the source code with collaborators and the community at large, and to stimulate some feedbacks and comments.

We are still working on improving this interface in order to use it with "industrial" grade meshes and large hydroturbine simulation problems. We will publish our improvements on a regular basis, so you have to expect some changes to the code (certainly) and to the dictionaries syntax (possibly) pertaining to the mixingPlane interface. So this source code should still be considered as experimental.

As of January 2012, the limitations of the current mixingPlane implementation (mixingPlane_RC1) are:

• Todo

1.6 Examples of dictionaries configuration

• constant/polyMesh/boundary

Todo

• field value dictionaries in the time directories

Todo

1.7 Specification of mixingPlane reference frame

Todo

1.8 Specification of the mixingPlane discretization profile

Todo

1.9 Running the mixingPlane in parallel

Todo

1.10 The mixingPlaneCheck functionObject

Todo

1.11 The checkMixingPlane utility program

Todo

1.12 Tutorials

• Simplistic examples
• The ERCOFTAC conical diffuser
• The ERCOFTAC centrifugal pump
• Simple rotor-stator examples

1.13 Test harness

Todo