How to implement the zonal (or layering) RANS and LES method

impecca · February 1, 2012, 06:43

Dear foamers

I am trying to implement a wall model which is known as zonal (or layering or two-layer) RANS and LES method. Papers related to this model are below

1. Wang and Moin, Dynamic wall modeling for large-eddy simulation of complex turbulent flows, Physics of Fluids, 2002

2. L. Temmerman, M. Hadžiabdic, M.A. Leschziner, K. Hanjalic, A hybrid two-layer URANS–LES approach for large eddy simulation at high Reynolds numbers, International Journal of Heat and Fluid Flow, Volume 26, Issue 2, April 2005, Pages 173-190,

In these models, simplified RANS equations need to be solved in the 'inner' or 'embedded' mesh which is different from global mesh for LES (global mesh means that the mesh which is saved in /constant/polyMesh/ folder). So I am wondering is there any way to deal with two different mesh and equations at the same simulation with its overlap area (the inner mesh overlaps on the global mesh) in OpenFoam? I really don't know where to start. if there is any prototype case or any other approach to cope with this issue that you know, please let me know. and any other advice will be very grateful.
Regards

Yusik

zht_shanghai · December 10, 2012, 22:52

Hi, Yusik.
I have exactly the same questions with you. So did your problems finally get solved? or you have other advice? Any reply will be appreciated, thanks.

vonboett · January 15, 2013, 11:05

Maybe of interest: Keylock et. al used that approach to model rivers and streams and they provide some suggestions for the grid resolution and several values for parameters used for the Reynolds averaged wall layer simulation, and of course all the equations:

Keylock et. al (2012) "The application of computational fluid dynamics to natural river channels:
Eddy resolving versus mean flow approaches" in Geomorphology 179 (2012) 1–20

I still work with wall functions or even just vanDriest Damping but I would be happy if someone gets further than that in OF.

ArpanS · March 10, 2017, 13:34

Hello everyone

I am trying to implement a similar methodology into OpenFoam. Specifically I am working on implementing non-equilibrium models in a refined embedded mesh close to the walls of IC engines to solve for wall heat transfer. Any pointers on how to get started with embedding such a mesh into the existing mesh, solving additional PDEs on the embedded mesh and passing information between the two meshes would be of great help.

Thanks
Arpan

huangxianbei · May 16, 2017, 23:52

To the best of my knowledge, the hybrid method contains both hard interface and soft interface between LES and RANS. Therefore, you may not need to split the mesh into 2 parts. Setting a appropriate y+ should be more convinient. While, the problem remains to solve the interface which couples the 2 methods. That's to say, the RANS field should increase fluctuation and LES should damping towards the interface. I'm interested in this topic, if you have any further research, I'm glad to communicate with you.

February 1, 2012, 06:43	How to implement the zonal (or layering) RANS and LES method	#1
impecca Member Kim Yusik Join Date: Dec 2009 Posts: 39 Rep Power: 17	Dear foamers I am trying to implement a wall model which is known as zonal (or layering or two-layer) RANS and LES method. Papers related to this model are below 1. Wang and Moin, Dynamic wall modeling for large-eddy simulation of complex turbulent flows, Physics of Fluids, 2002 2. L. Temmerman, M. Hadžiabdic, M.A. Leschziner, K. Hanjalic, A hybrid two-layer URANS–LES approach for large eddy simulation at high Reynolds numbers, International Journal of Heat and Fluid Flow, Volume 26, Issue 2, April 2005, Pages 173-190, In these models, simplified RANS equations need to be solved in the 'inner' or 'embedded' mesh which is different from global mesh for LES (global mesh means that the mesh which is saved in /constant/polyMesh/ folder). So I am wondering is there any way to deal with two different mesh and equations at the same simulation with its overlap area (the inner mesh overlaps on the global mesh) in OpenFoam? I really don't know where to start. if there is any prototype case or any other approach to cope with this issue that you know, please let me know. and any other advice will be very grateful. Regards Yusik

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Transition RANS to LES during simulation	LorenzN	OpenFOAM Running, Solving & CFD	4	November 17, 2011 11:47
Mapping RANS data onto an LES	christian	OpenFOAM Running, Solving & CFD	0	April 13, 2007 06:31
someone to answer..Difference between LES and RANS	Nik	Main CFD Forum	2	September 4, 2005 12:40
RANS results for LES	Li Yang	Main CFD Forum	5	June 17, 2002 06:34
use of common RANS B.C.'s in LES?	Sanjin Saric	Main CFD Forum	0	March 21, 2002 07:08

December 10, 2012, 22:52		#2
zht_shanghai New Member zhanghaitao Join Date: Apr 2012 Location: Shanghai Posts: 1 Rep Power: 0	Hi, Yusik. I have exactly the same questions with you. So did your problems finally get solved? or you have other advice? Any reply will be appreciated, thanks.

January 15, 2013, 11:05		#3
vonboett Senior Member Albrecht vBoetticher Join Date: Aug 2010 Location: Zürich, Swizerland Posts: 240 Rep Power: 17	Maybe of interest: Keylock et. al used that approach to model rivers and streams and they provide some suggestions for the grid resolution and several values for parameters used for the Reynolds averaged wall layer simulation, and of course all the equations: Keylock et. al (2012) "The application of computational fluid dynamics to natural river channels: Eddy resolving versus mean flow approaches" in Geomorphology 179 (2012) 1–20 I still work with wall functions or even just vanDriest Damping but I would be happy if someone gets further than that in OF.

March 10, 2017, 13:34		#4
ArpanS New Member Arpan Sircar Join Date: Mar 2017 Posts: 8 Rep Power: 9	Hello everyone I am trying to implement a similar methodology into OpenFoam. Specifically I am working on implementing non-equilibrium models in a refined embedded mesh close to the walls of IC engines to solve for wall heat transfer. Any pointers on how to get started with embedding such a mesh into the existing mesh, solving additional PDEs on the embedded mesh and passing information between the two meshes would be of great help. Thanks Arpan

May 16, 2017, 23:52		#5
huangxianbei Senior Member Huang Xianbei Join Date: Sep 2013 Location: Yangzhou,China Posts: 302 Rep Power: 14	To the best of my knowledge, the hybrid method contains both hard interface and soft interface between LES and RANS. Therefore, you may not need to split the mesh into 2 parts. Setting a appropriate y+ should be more convinient. While, the problem remains to solve the interface which couples the 2 methods. That's to say, the RANS field should increase fluctuation and LES should damping towards the interface. I'm interested in this topic, if you have any further research, I'm glad to communicate with you.