I notice that some udf's I have seen seem to access functions that I assume are defined as macros by fluent for users to implement. For instance, in a piece of a udf given to me that I am planning to use, the following two lines are written:

Compute_L_sgs(C_VOLUME(c,t),C_WALL_DIST(c,t),C_Cen troid_Y(c,t));

real S = Strainrate_Mag(c,t)

I see in the udf help manual what the functions C_VOLUME(c,t) means, however, I cannot find anywhere any documentation on C_WALL_DIST(), C_Centroid(), or Compute_L_sgs().

Where do I go to find details on each of these functions / variables? The udf manual seems to explain only a limited number of functions for access to the various solver variables?

Thanks in advance.

Good Luck!

Fluent hasn't (and probably won't) give a complete list of the internal variables used in Fluent and what they mean (in a way fair enough - what you're asking for is a complete documentation of the code structures).

However, if you know what you want to know (!!) then you can request this from Fluent. They generally provide the required functions etc.

Of course, we would all like to see more of the common functions/macros/variables documented more thoroughly. Just keep asking them.....

Alternatively post your questions here - some people know quite a lot. But the best resource, is Fluent.

Greg

Why not create an independent UDF function definition library available in an online library? Or would it be frowned upon by Fluent?