We’re putting the final touches on our new badges platform. Badge issuance remains temporarily paused, but all completions are being recorded and will be fulfilled once the platform is live. Thank you for your patience.
Fluids

Fluids

Topics related to Fluent, CFX, Turbogrid and more.

Quesiton about profile for fluent

    • lzfneu
      Subscriber

      Hi all,

      I intend to load heat generate rate to source term, which is in a cylinder shape.

      I try to write profile in r-phi-z format and the attachment is my transient profile file. The field I set is r, angle, z, respectively. Please help to check if I am right? and how to set the source term in cell zone conditions in cylinder coordinate.

      Thank you very much in advance.

    • Rob
      Forum Moderator
      Source terms are set via DEFINE_SOURCE or expressions, and (I think) are limited to x, y and z coordinates.
    • lzfneu
      Subscriber
      Thanks for your reply.
      The heat generate rate of source term in my problem is discrete values and is in cylindral coordinate. I want to consult you is there a method to perform this kind of heat transfer calculation in fluent.
      I have to find a method to import discrete values of heat generate rate which is in cylindral coordinate to source term so that I could do the next step water cooling calculation.
      Any suggestions or help will be appreciated, and thank you in advance.
    • Rob
      Forum Moderator
      Heat transfer calcs, yes, they're fairly routine.
      Using polar coordinates in code however isn't as we add sources based on position (x, y & z) as w, r and axial are relative. So, you'll need to convert the data in some way. If the data is being read to a UDF then you can convert the data as it's read in, or do the conversion externally then read the x, y & z position and it's attached data.
    • lzfneu
      Subscriber
      Thanks for your suggestions. I prefer your suggestion to do the conversion externally then read the x, y & z position and it's attached data.
      I want to confirm that if I am right: I intend to write the externally conversed data to profile and then read to my source term. The field in profile I use should be x,y,z and the attached data (heat generate rate).
      Thank you very much for your help.
    • Rob
      Forum Moderator
      Profiles are for surfaces. For source terms you'll need to read & assign the data into the source term so you'll need the file read functions and (possibly) some interpolation routines to add in values assuming the mesh & points don't line up.
    • lzfneu
      Subscriber
      Dear Rob Thanks for your reply.
      I want to import the heat generation rate (W/cm3) to the source term according to different x, y, z coordinations.
      For example, the heat generation is 1000W/cm3 in the location x=1.11cm, y=2.22cm, z=3.33cm; and is 2000W/cm3 in the location x=8.88cm, y=9.99cm, z=10.10cm; 3000W/cm3 in the location x=20.22cm, y=30.33cm, z=40.44cm;
      In order to achieve that, I write the source term as follows:
      #include "udf.h"
      DEFINE_SOURCE(test, c, t, dS, eqn)
      {
      real x[ND_ND];
      real a, b, c, source;
      C_CENTROID(x, c, t);
      a=x[0]; b=x[1]; c=x[2]; // x,y,z coordinate
      if(a==1.11 && b==2.22 && c==3.33) {source=1000;}
      if(a==8.88 && b==9.99 && c==10.10) {source=2000;}
      if(a==20.22 && b==30.33 && c==40.44) {source=3000;}
      dS[eqn]=0;
      return source;
      }
      Is it right?
      And is there any convinent method to use if there are many x, y, z coordiantes and heat generations, thank you very much in advance.
    • Rob
      Forum Moderator
      Sort of. You need to give the source a volume rather than a position so it'll be
      if( a>1.0 && a<1.2 && b.....
      Remember source terms are per m3 so be careful with the definitions.
Viewing 7 reply threads
  • The topic ‘Quesiton about profile for fluent’ is closed to new replies.