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

UDF vs Custom field function

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

Reply
 
LinkBack Thread Tools Display Modes
Old   October 9, 2007, 05:06
Default UDF vs Custom field function
  #1
andrew
Guest
 
Posts: n/a
Hi colleague,

I am currently writing up an equation that is to be input into fluent (for postprocessing)..i was wondering would i be able to fit this equation into the custom field function or should i write it in a udf and export it into fluent...using the custom field function would be a easier approach but i do not know the extend and how would the custom field function cope with the input of this equation...the equation that i would like to input in is:-

Sp=miu/T*(dUi/dxj+dUj/dxi)dUi/dxj

St=k(temperature_gradient)/T^2

thank you in advance...cheers

regards

andrew

  Reply With Quote

Old   October 9, 2007, 09:07
Default Re: UDF vs Custom field function
  #2
Woo Meng Wai
Guest
 
Posts: n/a
Hi Andrew,

I think in the custsom field function, you can the derivative of the velocities. However, there is no option for miu and temperature gradient. Not sure if you can implement this in the custom field function.

Woo
  Reply With Quote

Old   October 9, 2007, 10:51
Default Re: UDF vs Custom field function
  #3
andrew
Guest
 
Posts: n/a
hi Woo,

Yes u have the derivative function for the velocity...how about the temperature derivatives (temperature gradient)? any ideas for it? i am not sure when u use the solve/set/expert function will actually work...ps advice..thank you in advance

regards

andrew
  Reply With Quote

Old   October 9, 2007, 20:06
Default Re: UDF vs Custom field function
  #4
Woo Meng Wai
Guest
 
Posts: n/a
I think u have to advise me on this. I can't find the 'solve/set/advice function'

Do you find this under the 'solve' tab?

Woo

[my fluent version 6.3.26
  Reply With Quote

Old   October 10, 2007, 00:48
Default Re: UDF vs Custom field function
  #5
andrew
Guest
 
Posts: n/a
Hi woo,

i am also using the same version of fluent... Just type it in fluent after the > u should be able to get them..firstly key in solve and if u enter u will see the set variable and then enter...u will see the expert...after that there is a few question on yes or no that u need to get it before u could get the derivatives function for dT/dx dT/dy and dT/dz...hope that u will be able to get them...cheers
  Reply With Quote

Old   June 24, 2011, 10:53
Post derivative of the custom field function
  #6
New Member
 
osis
Join Date: Jun 2011
Posts: 8
Rep Power: 6
oghazian is on a distinguished road
is it possible to get the spatial derivative of the custom field function in fluent ??

or should I use UDF ??

thanks
oghazian is offline   Reply With Quote

Reply

Thread Tools
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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
channelFoam for a 3D pipe AlmostSurelyRob OpenFOAM 3 June 24, 2011 13:06
How to calculate pressure forces using custom field functions? tsagaro FLUENT 6 April 13, 2011 04:03
Custom Field Function fivep FLUENT 0 August 17, 2009 21:29
Error with Wmake skabilan OpenFOAM Installation 3 July 28, 2009 00:35
custom field function Meenu FLUENT 1 November 30, 2006 20:23


All times are GMT -4. The time now is 05:12.