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how to derive relative velocity in MRFSimpleFoam?

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Old   December 22, 2009, 23:26
Default how to derive relative velocity in MRFSimpleFoam?
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hi all,
as we known,the velocity derived from MRFSimpleFoam is absolute velocity,and my problem is that how can i derive relative velocity from it?

thanks
jennifer
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Old   December 22, 2009, 23:42
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Quote:
Originally Posted by renyun0511 View Post
hi all,
as we known,the velocity derived from MRFSimpleFoam is absolute velocity,and my problem is that how can i derive relative velocity from it?

thanks
jennifer
I will send you my utilities. which i remember i have ever send it to you before
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Old   June 30, 2010, 13:22
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Sunny William
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Hello Wayne,

I am simulating an impeller/diffuser stage case and I want to visualize the impeller relative velocity.

Could you kindly send me the utility too?

Many thanks,

San
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Old   February 8, 2011, 05:57
Default How to write relative velocity in MRFSimpleFoam
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Aldo Iannetti
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Quote:
Originally Posted by waynezw0618 View Post
I will send you my utilities. which i remember i have ever send it to you before
Hi
can you please send me your utilities to write relative velocity in MRFSimpleFoam?
Thanks
Aldo
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Old   February 13, 2011, 02:42
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Quote:
Originally Posted by aldo.iannetti View Post
Hi
can you please send me your utilities to write relative velocity in MRFSimpleFoam?
Thanks
Aldo
Attachment 6480

Good Luck

jennifer

Last edited by renyun0511; November 9, 2011 at 23:10.
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Old   February 13, 2011, 02:44
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Quote:
Originally Posted by Santana View Post
Hello Wayne,

I am simulating an impeller/diffuser stage case and I want to visualize the impeller relative velocity.

Could you kindly send me the utility too?

Many thanks,

San
Attachment 6481
Good Luck

jennifer
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Last edited by renyun0511; April 20, 2013 at 04:11.
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Old   March 22, 2012, 09:31
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Hi

I took the liberty of updating it to a more recent version of OF.

1.6-2.1.x to be exact.

I can see that from 1.6 and onwards the relativeVelocity have been part of the std MRF files so this makes the code much simpler as it is possible to call the relativeVelocity directly

Best
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File Type: gz Urel.tar.gz (1.4 KB, 97 views)
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Old   May 16, 2013, 04:27
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Here is one that works for OF-2.2.x

EDIT:
MRF has changed a lot in 2.2 and some solvers are using the MRFProperties file in the constant folder and some are using the system/fvOptions.

EDIT2:
Just place the MRFProperties file in the constant folder with the same info as the one from system/fvOptions then this new version works.
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File Type: jpg 2013-05-29-07-07-000021.jpg (34.1 KB, 87 views)
Attached Files
File Type: gz Urel-2.2.x.tar.gz (1.4 KB, 124 views)
File Type: txt MRFProperties.txt (1.1 KB, 126 views)
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Last edited by linnemann; May 29, 2013 at 03:11.
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Old   May 16, 2013, 05:17
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Originally Posted by linnemann View Post
Here is one that works for OF-2.2.x
Thanks very much linnemann! Its beautiful!

Regards
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Old   May 17, 2013, 09:23
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Quote:
Originally Posted by linnemann View Post
Here is one that works for OF-2.2.x
Hi, Linnemann,

Do you have the Urel Utilities for OF-2.1.0?

Thanks,

Yun Ren
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Old   May 17, 2013, 09:28
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Sorry, Ithink I find it. I ignored your upper message!

Quote:
Hi

I took the liberty of updating it to a more recent version of OF.

1.6-2.1.x to be exact.

I can see that from 1.6 and onwards the relativeVelocity have been part of the std MRF files so this makes the code much simpler as it is possible to call the relativeVelocity directly
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Old   May 27, 2013, 21:16
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Quote:
Originally Posted by linnemann View Post
Here is one that works for OF-2.2.x
Hi Linnemann,

Sorry,very late!I just made a plot over line to check this Urel.But its absolutely the same with U,see the image below,Urel(1) and U(1) coincide exactly.and its the same with U(2) Urel(2).Any ideas?Thanks for your reply!
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Old   May 29, 2013, 03:10
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Hi see post

how to derive relative velocity in MRFSimpleFoam?
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Old   July 8, 2014, 05:07
Default What does Urel do in true?
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Hi,

What does this Urel do in true? Regarding to the calculations done, I could find nothing. Is it just an updating of the mesh inside the MRF zone and then subtracting the velocities values from the "original" one?


Regards, Lisandro
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Old   September 7, 2014, 09:25
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Hello,

I compile successfully Urel (OpenFOAM 2.3.x) but when I run Urel after the calculation I see "No MRF models present" and Urel in exactly the same as U.

I have no problem with MRF during calculation, in log.simpleFoam I can see :

Code:
Creating finite volume options from "system/fvOptions"

Selecting finite volume options model type MRFSource
    Source: MRF1
    - applying source for all time
    - selecting cells using cellZone rotationCellZone
    - selected 1344433 cell(s) with volume 457.986

I add the MRFProperties.txt to the constant folder, is there something else to do to calculate Urel ?

Nolwenn
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Old   September 7, 2014, 13:00
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Hi

it should not be "MRFProperties.txt" but "MRFProperties"
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Old   September 7, 2014, 13:25
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Hi Niels,

Silly me ! Thank you, it works perfectly.

Nolwenn
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Old   January 13, 2015, 17:08
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I modified the Urel utility so that it reads fvOptions (version 2.3.0).
No need for MRFProperties anymore.
I called it "relU" to avoid confusion.
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Old   February 5, 2015, 05:58
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Can anybody tell to newbie how to install this utility?
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Old   June 2, 2015, 09:54
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Can anybody tell to newbie how to install this utility?


No one?
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