CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   OpenFOAM Meshing & Mesh Conversion (https://www.cfd-online.com/Forums/openfoam-meshing/)
-   -   [mesh manipulation] OpenFoam 2.1.0/x: creation of sets and cellZones. (https://www.cfd-online.com/Forums/openfoam-meshing/99331-openfoam-2-1-0-x-creation-sets-cellzones.html)

mm.abdollahzadeh June 17, 2012 20:49

Quote:

Originally Posted by samiam1000 (Post 362352)
Dear mm.abdollahzadeh,

does this allow you to have 2 fluid regions that have a coincident interface?

Dear Samuele

I am also a beginner in Openfoam. but i think it is possible. you can have more than one solid or fluid zones. But in diffrent situation you may need to modify the boundary condition

mm.abdollahzadeh June 17, 2012 20:51

Quote:

Originally Posted by Budlo (Post 362664)
Hi All

1-Why we use uniform value(300) in conjugate B.C ? (the conjugate boundary must to be solve)
What is diferent between: Compressible::turbulentTemperatureCoupledBaffleMix ed,
Compressible::turbulentTemperatureCoupledBaffle,

2- In chtMultiRegionFoam in OpenFoam 2011:
What is Ychar and Ypmma files in boundary condition ?

Dear namdar

I just know that the temperature that you are giving is an initial guess for the temperature of the wall to allow calculation of heat flux on diffrent side of interface.

ebah6 June 17, 2012 21:23

Thanks Jie for updating the thread.

my best regards.

samiam1000 June 18, 2012 03:22

Quote:

Originally Posted by mm.abdollahzadeh (Post 366930)
Dear Samuele

I am also a beginner in Openfoam. but i think it is possible. you can have more than one solid or fluid zones. But in diffrent situation you may need to modify the boundary condition

Dear Mahadi,

any idea about how to do this? Just an hint to begin..

Thanks,

Samuele

lovecraft22 June 18, 2012 05:37

Thank you Jie, that's great. But, how do you find the numbers to enter within the boundary file?

ebah6 June 18, 2012 07:16

Hi Lore,

The boundary file should be created automatically when you export to openFoam. The same thing with the other four files (faces, points, etc.)

Myself, I use pointwise. The only things I add to the boundary file after exporting from PointWise to OpenFoam are:
* to make sure I get cyclicAMI instead of just cyclic.
* the matchTolerance, the neighbourPatch, and the transform items.
Regarding the matchTolerance I think (but not sure) that it is at 1e-4 by default.
The neighbourPatch is the other of the pair rotor/stator. The example by Jie is explicit in this regard.

I hope this helps.

lovecraft22 June 18, 2012 07:21

Thank you ebah, so you don't need to set nFaces and startFace.

Also, what are the advantages of using pointwise (or any other software) compared to snappy? Can all of this be done using snappy only?

ebah6 June 18, 2012 07:32

I guess you can use snappy.
One thing is that if you are already familiar with a software pointwise or anyone else that can export to openFoam format, it save you some time.
Personally, I run into a bit of trouble with snappy, I couldn't solve it. So I switch to what I was a bit more familiar with.

Sorry, to answer to your question, even when you are using the OpenFoam embedded mesh generator with the blockMeshDict, all you deal with is this file; the boundary file and others are generated when you run the blockMesh command.

jiejie June 28, 2012 00:31

Hi Guys

Would you be able to share the set up for fvScehem and fvSolution when using AMI interface? I tried to re-use the propeller mesh from the GGI (openfoam-1.6-ext) with AMI (openfoam-2.1.1), but I found the simulation is very unstable with AMI (pressure solver is doing more than 400 iterations for every timestep), which is stable with GGI. I used the same fvScheme and fvSolution from the propeller tutorial for my case with AMI. I remember I did change some of the schemes with the GGI, but some of those schemes are not available in openfoam-2.1.1.

It will be really great if anyone can share some advice about this.

Thanks

Jie

mm.abdollahzadeh June 28, 2012 00:43

Dear Jie

Could you please tell me which solver of Openfoam you are using for turbomachinary?

I am new in Openfoam, and I want to model a rotor blade (NACA67).

Best
Mahdi

jiejie June 28, 2012 00:46

Hi Mahbi

I am just using the standard pimpleDyMFoam.

Jie

mm.abdollahzadeh July 23, 2012 08:35

Dear Samuel

if you have just two fluid zone with a interface between them. you can do this.

1-create the Mesh of each zone separately
2-Setup a running folder according to Chtmultiregion tutorial
( i mean create folders with the name of your zones and etc ... )
3-for creating coupled interfaces forexample for conjucate heat tarnafer , you should edit the type of your boundary condition in the boundary file in polymesh for each zone.
you need to replace it with :

type directMappedWall;
nFaces 350;
startFace 119925;
sampleMode nearestPatchFace;
sampleRegion Zone2; // name of the neighbor zone
samplePatch interfaceD; // name of the coincident boundary
offsetMode uniform;
offset (0 0 0);

4- then you need just to apply the correct boundary conditions in your Zero Folder.
for a scaler which is solving in both region and the interface boundary is coupled between the two zone you can use , turbulentTemperatureCoupledBaffleMixed.

Best
Mahdi

turbulencious August 1, 2012 11:59

hello Madi,

I found your last post here very relevant to the problem that I encounter. Can you elaborate more? I have followed the steps that you give here (change the boundary files in polyMesh from mappedWall to directMappedWall) but I find difficulties to chose a BC to couple the temperature between solid and fluid. My flow is laminar and I want to couple the temperature. When I use zeroGradient the temperature of the solid does not change at all

solver:chtMultiRegionFoam
version: OF-2.1.1

thank you very much in advance
cordially,
giorgos

mm.abdollahzadeh August 2, 2012 10:40

Quote:

Originally Posted by turbulencious (Post 374870)
hello Madi,

I found your last post here very relevant to the problem that I encounter. Can you elaborate more? I have followed the steps that you give here (change the boundary files in polyMesh from mappedWall to directMappedWall) but I find difficulties to chose a BC to couple the temperature between solid and fluid. My flow is laminar and I want to couple the temperature. When I use zeroGradient the temperature of the solid does not change at all

solver:chtMultiRegionFoam
version: OF-2.1.1

thank you very much in advance
cordially,
giorgos

Dear giorgos

So you can change the type of boudary to directmappedwall.
the next step is to use the follwing boundary conditions in 0 folder for temperature :
Example usage:

myInterfacePatchName
{
type compressible::turbulentTemperatureCoupledBaffle;
neighbourFieldName T;
K lookup;
KName K; // or none
value uniform 300;
}

or

myInterfacePatchName
{
type compressible::turbulentTemperatureCoupledBaffleMix ed;
neighbourFieldName T;
K lookup;
KName K;
value uniform 300;
}

Best
Mahdi

turbulencious August 8, 2012 04:05

thank you very much!

maHein August 13, 2012 12:12

When I try directMappedWall, I get an error message:

Code:

--> FOAM FATAL ERROR:

    patch type 'genericPatch' not type 'mappedPatchBase'
    for patch contact_fluid of field T in file "/disk401/home/heinri8/Simulation/FlatPlate/flatPlate_LTS/0/fluid/T"

    From function turbulentTemperatureCoupledBaffleMixedFvPatchScalarField::turbulentTemperatureCoupledBaffleMixedFvPatchScalarField
(
    const fvPatch& p,
    const DimensionedField<scalar, volMesh>& iF,
    const dictionary& dict
)

    in file derivedFvPatchFields/turbulentTemperatureCoupledBaffleMixed/turbulentTemperatureCoupledBaffleMixedFvPatchScalarField.C at line 99.

FOAM exiting

Looks like directMappedWall has been renamed to mappedWall in 2.1.0, (see official 2.1.0 release announcement)

sivakumar October 18, 2012 17:47

Hi Guys,
I have problem to create Sets and cellZones, I tried to follow Jiejie steps (he explained the steps in the previous post) .
while executing setSet, I am getting the following error,

Create time

Create polyMesh for time = 0

Time:0 cells:460000 faces:1402700 points:483021 patches:12 bb:(-1.06977 -0.559055 0.177709) (3.08761 0.0363306 0.771367)
cellSets:
fan size:0

cellZones:
fluid size:460000
faceZones:
default-interior size:1357300

Time = 0
mesh not changed.
Please type 'help', 'quit' or a set command after prompt.
readline>

I dont know why the cellSets: fan size 0
can you guys help me to sort out this problem.

Thanks for your time and answers,

Sivakumar

hfs November 12, 2012 15:45

Hello!

I have an STL and want to get faceZones according to it
how can I use setSet to do that?


Thank you!

reza1111 June 18, 2013 07:21

Hi everybody

I am new in OF and I am going to use AMI capability. my rotary interface isn't cylindrical.
my case is a rotary spheroidal zone in a cubic domain . can I do my case using OF?
Please give me some hints about AMI ability.
Thanks in advance,

Reza

reza1980 July 16, 2013 04:55

Hi All,
I hope you are fine. I am working on AMI to handle a propeller case through OF2.1x. My results seems not acceptable.
would you please let me your instruction to implement AMI.
I use this:

* Export two parts like Stator and Rotor from pointwise to OpenFoam
* Merge to parts as mergeMeshes Stator Rotor
* Update Boundary (Add cyclicAMi and tolerance)
* Use splitMeshRegions -makeCellZones -overwrite to make cellZones



Reza


All times are GMT -4. The time now is 05:19.