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

Some problems about UDF in fluent5.4

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 12, 2001, 13:24
Default Some problems about UDF in fluent5.4
  #1
Mark
Guest
 
Posts: n/a
Hi,Fluent Users: 1> I have a problem about my compiled UDF in fluent5.4.

In fluent UDF mannul,it is said "Copy Makefile.udf from the directory shown above to your library directory (e.g., libudf), and name it makefile",and "Copy makefile.udf from the directory shown above to your /src directory, and name it makefile".

But in my path/Fluent.Inc/fluent5.4 /src/,I have just makefile_nt.udf and user_nt.udf.So I consider makefile_nt.udf as Makefile.udf and user_nt.udf as makefile.udf.So I copy makefile_nt.udf to my library directory (e.g.,libudf), and name it Makefile,and copy user_nt.udf to my /src directory,and name it user_nt.

When I Compile or Link my Compiled UDF, I also type the complete path to the library directory. But I get the following error: Opening library "f:\guochuhybrid\wangyou\libudf\ntx86\2d\libudf.dl l"... Error: open_udf_library: couldn't open library: f:\guochuhybrid\wangyou\libudf\ntx86\2d\libudf.dll Error Object: ()

2> I have another problem,Do I need to set up 2D or 3D directories in my ultra?

3> The last problem is about the unit of pre-exponential factor in Arrhenius expression.

k=A*exp(-E/RT)

The unit of the forward rate constant for reaction k is m^3/(kmol-S).The unit of activation energy for reaction is J/kmol.The unit of universal gas constant is J/(kmol-K).Then E/RT is dimensionless.So the unit of pre-exponential factor(A) is m^3/(kmol-S).

But in fluent reactions pannel, pre-exponential factor(A) is dimensionless.And in literatures,the unit of pre-exponential factor(A) is 1/S.

Would you give me some advice about these?Any ansewer will be welcome.

Thank you.

Mark 2001.8.12

  Reply With Quote

Old   August 14, 2001, 00:07
Default Re: Some problems about UDF in fluent5.4
  #2
Greg Perkins
Guest
 
Posts: n/a
Check for the documentation on compiling udfs on NT. This process is different from on unix as outlined in the udf manual.

This is not so straightforward. It depends on the power that the concentration is raised to. In essence the total rate is

R = k * C^n

where C = kmol/m3

k = 1/(s-(kmol/m3)^(n-1))

R = kmol/m3-s

Greg
  Reply With Quote

Old   August 14, 2001, 09:03
Default Re: Some problems about UDF in fluent5.4
  #3
Mark
Guest
 
Posts: n/a
Hi,

Thank you for your reply.

I just have documentation on compiling udfs on UNIX Would you like to send me some copy about compiling udfs on NT?

Thank you.

  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
problems with UDF to set contact angle poiuy219 Main CFD Forum 0 April 30, 2009 11:43
UDF problems...FATAL ERROR! Paolo Lampitella FLUENT 1 September 8, 2005 11:07
DEFINE_DPM_OUTPUT macro UDF HELP Puneet FLUENT 3 November 28, 2003 11:55
DEFINE_ON_DEMAND UDF: How to declare A[ND_ND], etc jx FLUENT 1 November 6, 2003 18:23
UDF, UDF, UDF, UDF Luc SEMINEL Main CFD Forum 0 November 25, 2002 05:01


All times are GMT -4. The time now is 01:02.