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LRR(Launder-Reece-Rodi RSTM) turbulent model

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Old   November 27, 2013, 08:48
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Dr. B T KANNAN
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Quote:
Originally Posted by skeptik View Post
As i know, it's a common problem of the RSM-models.
But, possibly, bad convergence and non-physically solutions were reasoned by wrong boundary conditions. What is your case? Can you publish it?
Dear Skeptik,
Any success in axisymmetric jet case using LRR ?
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Old   November 28, 2013, 01:53
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Quote:
Originally Posted by skyinventorbt View Post
Dear Skeptik,
Any success in axisymmetric jet case using LRR ?
--
KANNAN
Really, i haven't understood your case.
But i have something to say about case settings.

1. You chose steady-state simulation. Do you know that in this case you get only rough solution?

try pisoFoam.

2. You should play with fvSchemes. Higher-order schemes are preferred, but you should balance in numerical stability and numerical scheme.
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Old   December 2, 2013, 09:22
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Quote:
Originally Posted by skeptik View Post
Really, i haven't understood your case.
But i have something to say about case settings.

1. You chose steady-state simulation. Do you know that in this case you get only rough solution?

try pisoFoam.

2. You should play with fvSchemes. Higher-order schemes are preferred, but you should balance in numerical stability and numerical scheme.
All I need is just a rough solution i.e. averaged values using steady state RANS LLR
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Old   August 6, 2014, 03:51
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Hello friends

I want to implement LLR model in OpenFOAM for micro-jet extracting device . It is asking

me to write R file.I have written that file. After that when I run the code parallaly It produce

floating point error in decomposePardict.

I am attaching you both log file and R file in zip format

Regards
harshawardha
Attached Files
File Type: zip micro_jet_1.zip (1.8 KB, 55 views)
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Old   November 22, 2016, 12:38
Default Reynolds Stress Model (for example LRR)
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Quote:
Originally Posted by skeptik View Post
I used to LRR in cyclone, so it had showed better results than k-eps both k-omega models.

I think it's a good model for special cases.
My case is a CYCLONE. I want to use Reynolds Stress Model (LRR) at OpenFOAM but I do not know how to use and define at the software.
To begin, I found a file R and changed it. My boundary conditions are inlet, outlet and walls.

File U is as fallow:
dimensions [0 1 -1 0 0 0 0];
internalField uniform (0 0 0);
boundaryField
{
walls
{
type noSlip;
}
inlet
{
type pressureInletOutletVelocity;
value uniform (-10 0 0);
}
outlet
{
type pressureInletOutletVelocity;
value uniform (0 0 0);
}
}

File R is as fallows:
dimensions [0 2 -2 0 0 0 0];
internalField uniform (0 0 0 0 0 0);
boundaryField
{
wallS
{
type kqRWallFunction;
value uniform (0 0 0 0 0 0);
}

inlet
{
type pressureInletOutletVelocity;
value uniform (0.0015325 0 0 0.0015325 0 0.00306504);
}

outlet
{
type zeroGradient;
}
}

According to the file U, What changes do I need on R?
Have you a file R to send to me?
I need the fvSolution and fvSchemes files for model LRR.

--> FOAM FATAL IO ERROR:
Cannot find patchField entry for walls

file: /home/dadehnegar/OpenFOAM/dadehnegar-4.0/run/project/MYcyclone/air+water/rsmLRR/0/R.boundaryField from line 25 to line 37.

According to the files U and R in above, help me to solve this error please.

Thanks
Ali
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Old   November 22, 2016, 13:36
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Dear skeptik,
I can not download your testcase in above. Please send me your CYCLONE case if possible. It will help me very much.

Thanks,
Ali
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Old   November 23, 2016, 04:46
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Quote:
Originally Posted by skeptik View Post
I used to LRR in cyclone, so it had showed better results than k-eps both k-omega models.

I think it's a good model for special cases.
Dear Skeptik,

I need your help.
Please send me your Email address.

Thanks,
Ali
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Old   November 23, 2016, 05:00
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Quote:
Originally Posted by ebtedaei View Post
Dear Skeptik,

I need your help.
Please send me your Email address.

Thanks,
Ali
Dear skeptik
I created R file and corrected it. Now, my problem is at the fvSchemes as fallow:

--> FOAM FATAL IO ERROR:
[0] keyword div(phi,R) is undefined in dictionary "/home/ebtedaei/OpenFOAM/ebtedaei-4.0/run/project/MYcyclone/air+water/rsmLRR/system/fvSchemes.divSchemes"
[0]
[0] file: /home/dadehnegar/OpenFOAM/ebtedaei-4.0/run/project/MYcyclone/air+water/rsmLRR/system/fvSchemes.divSchemes from line 30 to line 35.
[0]


Please send a fvSchemes file for LRR model and your Email address.

Thanks
Ali
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Old   December 27, 2017, 16:14
Default lrr simulation
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Quote:
Originally Posted by skeptik View Post
Here you can download cyclone- testcase
Please can you share again the file?
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Old   November 19, 2018, 19:28
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Quote:
Originally Posted by skeptik View Post
Here you can download cyclone- testcase
Hi,
can you please upload this file again as it is un available?

Last edited by Maahs; November 19, 2018 at 19:30. Reason: language mistake
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