CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM

Dissabling turbulent dissipation

Register Blogs Community New Posts Updated Threads Search

Like Tree2Likes
  • 1 Post By lindner
  • 1 Post By santos

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 14, 2010, 04:10
Default Dissabling turbulent dissipation
  #1
Member
 
Join Date: Mar 2010
Posts: 42
Rep Power: 16
lindner is on a distinguished road
Hi all,
I have a solver that calculates the local mean age of air, it's the simpleFoam solver with a scalarTransportFoam with source term = 1.
The code of the scalar transport is this

fvScalarMatrix ageEqn
(
fvm::ddt(age)
+ fvm::div(phi, age)
- fvm::laplacian(turbulence->nuEff(),age)
==
dimensionedScalar("ageSource", age.dimensions()*dimensionSet(0,0,-1,0,0), 1)
);

ageEqn.solve();

Now i want to test the local mean age solver but turning off the turbulent dissipation (turbulence->nuEff = 1).
I tried just removing the term from the equation but it didnt work. Is there a way to simple make the turbulent dissipation = 1 or add a simple constant?

Thanks
pemesu likes this.
lindner is offline   Reply With Quote

Old   July 14, 2010, 10:16
Default
  #2
Senior Member
 
santos's Avatar
 
Jose Luis Santos
Join Date: Mar 2009
Location: Portugal
Posts: 215
Rep Power: 18
santos is on a distinguished road
Send a message via Skype™ to santos
Hi there,

What if you replace it with:
- fvm::laplacian(Dage,age)
where Dage is the diffusivity of age (dont know whether it make sense!)

Dage will have to be declared in createFields.H, and then defined in constant/transportProperties.

Regards,
Jose Santos
pemesu likes this.
santos is offline   Reply With Quote

Old   July 15, 2010, 04:48
Default
  #3
Member
 
Join Date: Mar 2010
Posts: 42
Rep Power: 16
lindner is on a distinguished road
it worked!
Thanks for the help Jose, the code was implemented successfully.

Guilherme
lindner is offline   Reply With Quote

Old   February 7, 2021, 13:51
Default
  #4
HPE
Senior Member
 
HPE's Avatar
 
Herpes Free Engineer
Join Date: Sep 2019
Location: The Home Under The Ground with the Lost Boys
Posts: 932
Rep Power: 12
HPE is on a distinguished road
Set the term `alphaDt` to zero in these code blocks to turn off the turbulent diffusion contributions into the local mean age of air: Age of Air Function Object
HPE is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Turbulent intensity and turbulent dissipation Phil FLUENT 2 February 14, 2018 05:06
turbulent kinetic energy and turbulent dissipation rate D_L Main CFD Forum 5 July 17, 2010 02:35
turbulent dissipation rate pluto STAR-CCM+ 3 November 11, 2009 14:41
Turbulent Eddy Dissipation in LES Patrick CFX 8 July 12, 2006 02:44
calculation of (turbulent) dissipation energy ? max Main CFD Forum 3 August 18, 1999 09:42


All times are GMT -4. The time now is 18:06.