yPlusLES: compressible flow
 

Hi All ,

I am new to openFOAM. I just finished a compressible LES with OpenFOAM. When I want to use yPlusLES to calculate the y+ in my case, I got the messege to provide nuSGS. I think this quantity is only for incompressible flows. Could anyone know how to calculate the y+ in compressible flows?

Thank you so much!

Hi openfoammaofnepo,

I managed to remember two details:

1. The yPlusLES and yPlusRAS should both have the "-compressible" option, but I've taken a look into it and only the yPlusRAS has got one. You can check by running:
   
   Code:

   ---

   yPlusRAS -help

   ---

2. This problem isn't new. You can calculate yPlusLES in a compressible simulation, by using a function object, while the solver is running. For more information about this and the report about the missing feature: http://www.openfoam.org/mantisbt/view.php?id=802

Best regards,
Bruno

Thank you wyldckat!

I am using OF211, but this problem has been fixed in OF210 maybe.

Hi openfoammaofnepo,

I forgot to mention the version... In OpenFOAM 2.2.0 you can use yPlusLES as a function object in a compressible simulation, as indicated here: http://www.openfoam.org/version2.2.0...processing.php - this link is shown in the other link in the previous posts.

As for yPlusLES application itself, it has not yet been fixed to use compressible, not even in OpenFOAM 2.2.x, which is the very latest bug fix version of OpenFOAM.

Best regards,
Bruno

Thank you wyldckat.

If I would like to calculate yPlus for compressible LES using OF211, how can I do it? Could you please give me some hints?

thanks.

Hi openfoammaofnepo,

I've made a note to look into this next week.

In the mean time, have a look into the source code of the "yPlusLES" application in your own OpenFOAM version. You can find it by running this command:
Then compare with the source code on OpenFOAM 2.2, namely this file: https://github.com/OpenFOAM/OpenFOAM...LES/yPlusLES.C - compare the methods "calcIncompressibleYPlus" with "calcCompressibleYPlus", with the ones on the application you've got.

As to modifying an OpenFOAM application, check this tutorial: http://openfoamwiki.net/index.php/Ho...ure_to_icoFoam

Best regards,
Bruno

Hi openfoammaofnepo,

Done! I've created the "yPlusLESWCompressible" utility for OpenFOAM 2.2.x and then back-ported to 2.1.x. Simply follow the instructions given here https://github.com/wyldckat/yPlusLES...swcompressible

Hopefully everything will work as intended. At least the tests I've made seemed to indicate that everything was OK.

Best regards,
Bruno

Can not get some post processing
 

Good afternoon,

I tried to get the y+ or the wall shear stress, in order to put some probes for some tests, but unsuccessfully.
The simulation I did, was compressible LES, and the OpenFOAM version I am using is the 2.0.1 (maybe where the problem is).
I tried to compute y+ with the command yPlusLES but it gave me this error:

I saw the previous posts, and typed for the compressible case, but it said it was an invalid option. And I also saw the code, and seeing that the transport properties is used for incompressible, I think my version does not have the possibility to compute y+ for compressible flow in this way.

Is it possible to get what I need, without running the simulation again ? And if so, will I need the function object ?

(Doing an upgrade in my version will be complicated.)

Greetings guilha,

Try following the latest instructions given here: https://github.com/wyldckat/yPlusLES...ble/tree/of210

Best regards,
Bruno

Hi Bruno,

Thank you very much for your help.

When I compiled it using wmake yPlusLESWCompressible, I got the following information:

make: *** No rule to make target `yPlusLESWCompressible'. Stop.

Do I need to add something in the Make folder? Thank you very much.

http://www.cfd-online.com/Forums/ope...tml#post376918

Zou can also have a look at this thread.

Hi wyldckat,

Sorry to bother you. Could you please give me some suggestions about how to compile the yPlusLESWCompressible package? When I compiled it I had the problem I mentioned in the last thread. I am not very familiar with C++ compilation. Thank you and happy new year!

Greetings to all!

@owayz: :eek: I had no idea someone else had already provided a compressible y+ for LES!

@openfoammaofnepo:
I need to know:

1. The exact instructions you have followed to try and install "yPlusLESWCompressible".
2. Which exact version of OpenFOAM are you using and how you installed it.
3. Which Linux Distribution are you using.
4. What is the complete output that you get. That last error message is far from enough to figure out what's wrong :(.

Best regards,
Bruno

Hi,

1, The install procedure is from the following:

https://github.com/wyldckat/yPlusLES...swcompressible

I put the install package in the folder:
/users/openfoammaofnepo/OpenFOAM/openfoammaofnepo-2.1.1/utilities/yPlusLESWCompressible-of21x/yPlusLESWCompressible

2, The OF version is 2.1.1
3, the Linux version is Distributor ID: ScientificSL
Description: Scientific Linux SL release 5.5 (Boron)
Release: 5.5
4, The complete output info is (after inputting the command wmake yPlusLESWCompressible)
make: *** No rule to make target `yPlusLESWCompressible'. Stop.

Thank you very much.

Hi openfoammaofnepo,

:eek: OK OK, got it. You did not perfectly follow the instructions written on the page ;)
Whoops... and I forgot to write the command for unzipping it :( That explains why you didn't perfectly follow the instructions :( Sorry about that.

OK, the exact instructions should be:
The detail here is that you are running the wmake command from within the folder "yPlusLESWCompressible" and not from its parent folder. This is why you get that error message.

You have two possible solutions:

1. While you are still within the folder "yPlusLESWCompressible-of21x/yPlusLESWCompressible", simply run:
   
   Code:

   ---

   wmake

   ---

2. Or while you are still within the folder "yPlusLESWCompressible-of21x/yPlusLESWCompressible", go back to the parent folder and build as originally described. In other words, run:
   
   Code:

   ---

   cd ..
wmake yPlusLESWCompressible

   ---

Best regards,
Bruno

Hi wyldckat, successfully installed. Thanks.

Hi wyldckat,

When we run wmake in the folder yPlusLESWCompressible-of21x/yPlusLESWCompressible, which file or executable is run for this command? Thank you very much.

Hi openfoammaofnepo,
I'm not sure I understand your question, because the "obvious" answer would be: it's wmake, it's a script that will take care of building the application on demand. You can find more information about this in the User Guide: http://www.openfoam.org/docs/user/co...plications.php

Best regards,
Bruno

Dear Bruno,

When I run yPlusLESWCompressible -compressible, I found that there is an error information about my thermodynamics option:

The version of OF is 2.1.1, and I think the thermodyanmic library should be fine for my case. But I am not sure why this error comes from. Do you have the problem when you use it? Thank you so much.

Hi openfoammaofnepo,

I need more specific information on how you have configured the "thermodynamicProperties" file and how you load your customized thermodynamics library.

Best regards,
Bruno