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vonkam April 17, 2013 10:38

read parameters into UDF
Hello everybody,

does anybody has ideas about filling a UDF at start of simulation with parameters, so I don't have to rebuild the library when I change a parameter in UDF?


vasava April 18, 2013 02:38

1. Do you mean that you want to write a UDF that modifies by itself?
2. Are you writing these UDF(s) for transient or steady-state simulations?

vonkam April 18, 2013 03:20

ad 1) My original idea was to load a file of parameters into UDMemories, that would be used by all cells or any other way to stuff the UDF without need to changing it. That would require a new compilation, i guess.
ad 2) Ideally both, but that also depends on the demands on memory. I think I can live with steady state simulation only.
Thanks for any help.

coglione April 19, 2013 03:26

Have a look at the UDF-Manual ->Scheme Macros. I think that's what you need.


billwangard April 19, 2013 16:00

UDF Parameters
The way to do this is to define an rpvar. Once created in the CASE, rpvars are saved with the case file.

Rpvars are variables that can be passed to the UDF routines. Thus, you can easily modify the UDF without recompiling. Rpvars can be changed from the FLUENT GUI panel using simple scheme commands.

Look in the UDF manual on how to do this. If you need an example, please contact me directly:

Bill Wangard
Engrana LLC

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