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

How to make parameter option in turbulent model constants

Register Blogs Members List Search Today's Posts Mark Forums Read

Like Tree1Likes
  • 1 Post By vinerm

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 31, 2020, 05:05
Default How to make parameter option in turbulent model constants
  #1
New Member
 
Jae Hyeon Bae
Join Date: Mar 2020
Posts: 4
Rep Power: 6
Baejh is on a distinguished road
Hi everyone!
I study about SST transition model coefficients effect on flat plate using sensitivity analysis.
So I have to simulate about 100 case changing coefficients.
For convenience, I want to set parameter about model coefficients.
In my fluent version(18.2), turbulent model coefficients can't make parameter setting like inlet condition(e.g. velocity magnitude).
Is there other fluent version to make parameter setting or other way to macro?

Thank you for reading my question
Baejh is offline   Reply With Quote

Old   March 31, 2020, 09:27
Default Model Coefficients
  #2
Senior Member
 
vinerm's Avatar
 
Vinerm
Join Date: Jun 2009
Location: Nederland
Posts: 2,946
Blog Entries: 1
Rep Power: 35
vinerm will become famous soon enough
By model coefficients, are you referring to physical model, i.e., coefficients used by the turbulence model or do you mean some boundary or initial conditions for turbulence?

Both can be controlled via commands, however, where will you get 100 values for coefficients of the turbulence model?
__________________
Regards,
Vinerm

PM to be used if and only if you do not want something to be shared publicly. PM is considered to be of the least priority.
vinerm is offline   Reply With Quote

Old   April 1, 2020, 06:34
Default
  #3
New Member
 
Jae Hyeon Bae
Join Date: Mar 2020
Posts: 4
Rep Power: 6
Baejh is on a distinguished road
Dear vinerm, Thank you for your response.

I mean turbulence closure coefficients like Ca1, Ca2 ,.. in SST transition model.
Make the about 100 cases changing the closure coefficients and get the result like skin friction(QOI) from each cases.
So I want to know how to change the model coefficients each case automatically(like macro).
Baejh is offline   Reply With Quote

Old   April 1, 2020, 07:42
Default Model Coefficients
  #4
Senior Member
 
vinerm's Avatar
 
Vinerm
Join Date: Jun 2009
Location: Nederland
Posts: 2,946
Blog Entries: 1
Rep Power: 35
vinerm will become famous soon enough
Those can be changed easily using rpsetvar, however, do note that those are not meant to be changed drastically or without any logic.

Command to change an rp variable is

(rpsetvar '<variable name> new-value)

e.g., if you want to change Ca1 from 2 to 2.1, you may do it like

(rpsetvar 'trans-sst-ca1 2.1)

For variables that are enabled only with transition model, you have to use trans in front of their name, such as, in the example above. For those that are native to SST model, you can call those without trans, such as, \beta_{i1} is called sst-beta-i1

Remember that parentheses are part of the command.
Baejh likes this.
__________________
Regards,
Vinerm

PM to be used if and only if you do not want something to be shared publicly. PM is considered to be of the least priority.
vinerm is offline   Reply With Quote

Old   April 2, 2020, 00:32
Default
  #5
New Member
 
Jae Hyeon Bae
Join Date: Mar 2020
Posts: 4
Rep Power: 6
Baejh is on a distinguished road
Thank you so much How to change the closure coefficient!
I will try to make a case for this way.
Baejh is offline   Reply With Quote

Reply

Tags
parameter study, sensitivity analysis, transition sst

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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
mass flow in is not equal to mass flow out saii CFX 12 March 19, 2018 05:21
Simple piston movement in cylinder- fluid models arun1994 CFX 4 July 8, 2016 02:54
Low torque values on Screw Turbine Shaun Waters CFX 34 July 23, 2015 08:16
Overflow Error in Multiphase Modelling with Two Continuous Fluids ashtonJ CFX 6 August 11, 2014 14:32
Low Mixing time Problem Mavier CFX 5 April 29, 2013 00:00


All times are GMT -4. The time now is 12:20.