[chegdan]

So I had a look at the file and yes ParaView Opens this fine. However, just some notes.

Just looking at the file itself

solid PIPE                                                                     |�����åb`A���C�b`A�C
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≩zD��P���6H�AP��C6H�A���C�b`A��?�K,=���C�b`AzD���C�b`AP��C6H�A�����åb`AP���6H�A���C�b`A?��e<���C�b`AzD�C
≩zD���C�b`A�����|(B��C|(BP��C6H�A�^?P��C6H�AzDP��C6H�A��C|(B��P���6H�A���|(BP��C6H�A��?�K,=���C�b`AzDP��C6H�AP��C6H�AzD���m�í�_B�m�C��_B��C|(Bp�~?p��=��C|(BzD��C|(B�m�C��_B�����|(B�m�í�_B��C|(B�^?P��C6H�AzD��C|(B��C|(BzD�����ÈʋB���C�ʋB�m�C��_B��}?}�>�m�C��_BzD�m�C��_B���C�ʋB���m�í�_B���ÈʋB�m�C��_Bp�~?p��=��C|(BzD�m�C��_B�m�C��_BzD���w�æ��B�w�C���B���C�ʋB��|?KZ>���C�ʋBzD���C�ʋB�w�C���B�����ÈʋB�w�æ��B���C�ʋB��}?}�>�m�C��_BzD���C�ʋB���C�ʋBzD��D2����BD2�C��B�w�C���B��{?ƪ9>�w�C���BzD�w�C���BD2�C��B���w�æ��BD2����B�w�C���B��|?KZ>���C�ʋBzD�w�C���B�w�C���BzD��e���=��Be��C=��BD2�C��B#[z?�U>D2�C��BzDD2�C��Be��C=��B��D2����Be���=��BD2�C��B��{?ƪ9>�w�C���BzDD2�C��BD2�C��BzD��i�����Bi�C���Be��C=��B�x?1�q>e��C=��BzDe��C=��Bi�C���B��e���=��Bi�����Be��C=��B#[z?�U>D2�C��BzDe��C=��Be��C=��BzD���:���j
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It seems like an ASCII with the words "SOLID" but it is not the right encoding. Doing a dos2unix command does nothing...and it just seems to be a malformed STL. For now, just do

surfaceMeshConvert cylinder.stl cylinderConvert.stl

then an ASCII format is create and the GUI will read this. I will investigate more, thanks for the example.

[Jetfire]

@chegdan

Thanks a lot!, following your steps i was able to import the stl file in helyx and simulate the flow.


After this i moved on to simulate flow over a rotating compressor. procedure followed was

1. created new case on helyx
(as soon as i create a new case Vtkerror.txt file gets created showing

ERROR: In /home/stefano/VTK5/SRC/IO/vtkOpenFOAMReader.cxx, line 4636
vtkOpenFOAMReaderPrivate (0x7f51cc0161f0): Error opening /home/eatin/OpenFOAM/Engys/HELYX-OS/v2.1.1/compressor/constant/polyMesh/faces.gz: Can't open. If you are trying to read a parallel decomposed case, set Case Type to Decomposed Case.


ERROR: In /home/stefano/VTK5/SRC/Filtering/vtkExecutive.cxx, line 756
vtkCompositeDataPipeline (0x7f51cc010f40): Algorithm vtkPOpenFOAMReader(0x7f51cc0121b0) returned failure for request: vtkInformation (0x7f51cc018ed0)
Debug: Off
Modified Time: 17103
Reference Count: 1
Registered Events: (none)
Request: REQUEST_DATA
ALGORITHM_AFTER_FORWARD: 1
FORWARD_DIRECTION: 0
FROM_OUTPUT_PORT: 0




ERROR: In /home/stefano/VTK5/SRC/Common/vtkLookupTable.cxx, line 117
vtkLookupTable (0x7f51cc02aa60): Bad table range: [0, -1] )

ignored this and proceded further


2. copied the stl file of compressor (original.stl downloaded from Grabcad) in const/triSurface

3. created surfaceFeatureExtractDict in the system folder with the code

FoamFile
{
version 2.0;
format ascii;
class dictionary;
object surfaceFeatureExtractDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

original.stl
{
extractionMethod extractFromSurface;

extractFromSurfaceCoeffs
{
includedAngle 100;
}

subsetFeatures
{
nonManifoldEdges yes;

openEdges yes;
}

writeObj yes;
}
4. ran surfaceFeatureExtract to generate original.emesh , imported original.stl and original.emesh on helyx successfully , created bounding box.
The mesh got created without any errors , but running checkMesh showed failed 1 mesh check.

Checking geometry...
Overall domain bounding box (-1 -1 -1) (1 1 1)
Mesh (non-empty, non-wedge) directions (1 1 1)
Mesh (non-empty) directions (1 1 1)
Boundary openness (-1.26128706e-16 -6.985468702e-17 8.911002677e-18) OK.
Max cell openness = 2.893974403e-16 OK.
Max aspect ratio = 6.900018596 OK.
Minimum face area = 5.995107789e-06. Maximum face area = 0.01015167571. Face area magnitudes OK.
Min volume = 8.184337168e-08. Max volume = 0.001017196199. Total volume = 7.997283095. Cell volumes OK.
Mesh non-orthogonality Max: 64.94573455 average: 15.08810976
Non-orthogonality check OK.
Face pyramids OK.
***Max skewness = 5.16699312, 7 highly skew faces detected which may impair the quality of the results
<<Writing 7 skew faces to set skewFaces
Coupled point location match (average 0) OK.

Failed 1 mesh checks.

End

Can you please help me with this and also let me know if these kind of rotating turbomachinery simulations can be done on helyxOS v2.1.1.
Thanks.

[chegdan]

@Jetfire

Sorry for the late reply, this isn't necessarily a question on HELYX-OS....its more of a snappyHexMesh question. In general most errors in snappy are fixed by reducing the base mesh size; making the base mesh size cubic instead of rectangular prism; and/or increasing the levels on a surface to refine where bad cells may form. If you are new to using snappy, I suggest a few talks located on the OpenFOAM wiki

Tutorials and Guides

and that should help. For the most part, let HELYX-OS set the quality metrics for you as they are good all-around settings. Good luck. If you are still having issues then i suggest you start a new thread more specific to the case. Good Luck.

[Jetfire]

@chegdan

Thanks for your reply. will surely go through OpenFoam tutorials and guides

[chegdan]

Originally Posted by Jetfire

@chegdan

Thanks for your reply. will surely go through OpenFoam tutorials and guides

No problem. These aren't the standard guides.....but more snappyHexMesh specific and some with suggestions on getting improved meshes out of SHM.

[vishnuhp444]

I am working on HELYX-OS 2.1.1 on Ubuntu 12.04 64bit platform.

1) I am dealing with steady state and unsteady rotating machinery problems with two regions (rotating and stationary). So, I am required to use cylicAMI boundary condition. Unlike in the CSTR impeller tutorial, I would like to use surfaceInterfaces (cyclicAMI) in place of cylinder in the cell zone. . But this seems to be giving me problems. Please provide me instruction on creating surfaceInterface patches with cyclicAMI boundary condition.

2) Bounding box- Is it possible to combine multiple meshes created by HELYX-OS. Different regions require different refinement in the same problem. Would this cause any geometrical/meshing issues?I combined two meshes using mergeMeshes command but this seems to be giving me issues.

Please help. Thanks in advance.

VISHNU HARIPRASAD

[Jetfire]

Even I'm working on rotating body simulations on HelyxOS v2.1.1, the basic of all being flow over a rotating cylinder. I too have lots of problems using MRF with cyclicAMI Interfaces for this case, Can someone help me with this.

Thanks

[Jetfire]

Hi izna,

I get the same error when i run foamInstallationTest in my terminal
Executing /opt/openfoam221/bin/foamInstallationTest:


Checking basic setup...
-------------------------------------------------------------------------------

FATAL ERROR: OpenFOAM environment not configured.

Please refer to the installation section of the README file:
<OpenFOAM installation dir>/OpenFOAM-2.2.1/README
to source the OpenFOAM environment.


Did you figure out how to solve this problem??

[chegdan]

@jetfire,

Greetings!

You wrote that you are using OpenFOAM-2.2.1 but are using HELYX-OS v2.1.1. Unfortunately, the newest version of HELYX OS works with OpenFOAM-2.3.0. This is probably one of the reasons you are having issues since there have been changes that may influence your meshing that have changed from OF-2.2.1 to OF-2.3.0.

For the MRF, you will need to create a cell zone from a primitive (e.g. cylinder) and name the zone.

1. In the tree, under geometry, choose the object that will enclose your cell zone that will rotate.
2. locate the zones tab to the right of the tree
3. change the type to something like boundary
4. check the cell Zone box to create the cell zone.

This will create a cellzone that you can refer to when defining the rotating region within the caseSetup > cell zones portion of the GUI.

Your last error from foamInstallationTest was not clear. Please copy and paste the error here (enclosed by [CODE]) like

[CODE]
insert code or text from log files
[CODE]

but for the closing [CODE], instead put /CODE inside the square brackets (i can't do that here or it would not be visible)

[vishnuhp444]

Hi Chegdan

Thanks for the reply. I have been running HELYX-OS 2.1.1 using OPENFOAM 2.2.x. I was able to run the steady-state case with the .stl blade geometry and cylindrical cell zones without any issue. But, I have been trying to implement the same problem in unsteady mode. I have found that creation of interfaces (for cyclicAMI) removes several geometry features from the .stl file. It even removes the computational domain created.

1) Could this be because of the version problem you mentioned earlier?
2) I have found that defining 'number of elements' for the bounding box to be trial and error. For example, if I change the 'number of elements' from 55 to 56, it gives me an error. Is there any standard way to define this parameter?
3) Could you tell me what are 'internal', 'boundary' and 'baffle' zones?

Regards

VISHNU HARIPRASAD

[chegdan]

Just a quick reply to your questions:

1. try posting some of the error messages or a test case and I can take a look.
2. This should be fine. what sort of errors are you receiving? ultimately, the base mesh should be composed of cubes and not rectangular prisms in order to snap better. if this is a case of HELYX-OS giving an error, please post your steps to reproduce.
3. see the following page and look for the discussion towards the bottom

[Jetfire]

Hii chegdan,
Sorry for the late reply,


Thanks for taking your time to help me out. I get this error when i run foamInstallationTest.

FATAL ERROR: OpenFOAM environment not configured.

    Please refer to the installation section of the README file:
    <OpenFOAM installation dir>/OpenFOAM-2.2.1/README
    to source the OpenFOAM environment.

I'm planning to install OpenFOAM 2.3.0 as per your suggestions as it better works with Helyx 2.1.1. Can 2 versions of OpenFOAM be installed on the same system?

Regarding the MRF, I will try following the steps suggested by you and revert back in case of any queries.

Thank you .

[Jetfire]

Originally Posted by chegdan

@jetfire,

For the MRF, you will need to create a cell zone from a primitive (e.g. cylinder) and name the zone.

1. In the tree, under geometry, choose the object that will enclose your cell zone that will rotate.
2. locate the zones tab to the right of the tree
3. change the type to something like boundary
4. check the cell Zone box to create the cell zone.

Hi chegdan,

I tried simulating a rotating box , Please refer to the images below.
Under the boundary conditions i get these patches:

1.box_region0 ( should i define it as fixed wall or moving-rotating wall with same angular velocity as rotor?)
2.rotor_region0
3.rotor_region0_slave.( merged these 2 patches with cyclicAMI, not sure which type rotational/coupling)
I'm unsure what conditions i should be specifying for these patches.Could you please help me with this.

Thanks

[chegdan]

Can 2 versions of OpenFOAM be installed on the same system?

Yes, they will have different names like OpenFOAM-2.2.1 or OpenFOAM-2.3.x . In HELYX-OS you will need to go to edit>preferences to change where HELYX-OS is pointing towards. Good luck.

[JR22]

Hi,

It is pretty cool that we can call ParaView from Helyx-OS. In the attachment, is an image with my preferences to get the Paraview executable called.

How do I call the parallel version of it? Equivalent to the following command:

paraFoam -builtin

[JR22]

Figured it out, when you open Paraview, just use the "Decomposed case" in the Properties tab (below the Refresh) button.

Originally Posted by JR22

Hi,
It is pretty cool that we can call ParaView from Helyx-OS. In the attachment, is an image with my preferences to get the Paraview executable called.
How do I call the parallel version of it? Equivalent to the following command:

paraFoam -builtin

[Norris]

Hello all. When using a volumetric flow rate as your input in the Helyx gui, the pressure input box still shows. What should the value be set to and what should I set my outlet to? A negative flow rate? Also, are there any validation studies that have been done? I've tried applying a volumetric flow to one end of a straight pipe but the resulting velocity is too low by a factor of four (pretty consistently). I think i may be setting up the inputs incorrectly. Thanks for help in advance!

Marshall

[chegdan]

Marshall,

if you attach a link to a test case that I can open in HELYX-OS I'll take a look and see if find any issues.

[Norris]

Dan,

my case can be located here:
https://www.dropbox.com/s/352wxj3quj...se.tar.gz?dl=0

Also, every time I update my inputs and rerun the case, I am getting duplicate results files. I have found that I can remesh and it deletes the previous results. Is there another way to remove previous case results? Thanks for you help.

Marshall

[chegdan]

Took a look at the case and I have a few suggestions:

1. Set you inlet pressure to zeroGradient
2. remesh the whole geometry since the pipe surface cells are not really snapped, you have collapsed layers everywhere. make your base mesh smaller and this will help tremendously.

I'm not sure about he duplicate results, I am not seeing that behavior. With regard to removing old results, as long as start time is set to 0 (or wherever you intend to start and overwrite) then the results are overwritten. Remeshing will remove all the fields & mesh and start over completely.