read parameters into UDF

vonkam · April 17, 2013, 10:38

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?

Thanks
Michal

vasava · April 18, 2013, 02:38

Questions:
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.

cheers

billwangard · April 19, 2013, 16:00

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.com

Regards,
Bill Wangard
Engrana LLC

April 17, 2013, 10:38	read parameters into UDF	#1
vonkam New Member Michal Vonka Join Date: Apr 2013 Posts: 5 Rep Power: 13	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? Thanks Michal

April 19, 2013, 03:26		#4
coglione Senior Member Max Join Date: Mar 2009 Posts: 133 Rep Power: 17	Have a look at the UDF-Manual ->Scheme Macros. I think that's what you need. cheers vonkam likes this.

April 19, 2013, 16:00	UDF Parameters	#5
billwangard New Member Bill Wangard Join Date: Jan 2011 Posts: 21 Rep Power: 0	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.com Regards, Bill Wangard Engrana LLC

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April 18, 2013, 02:38		#2
vasava Senior Member Paritosh Vasava Join Date: Oct 2012 Location: Lappeenranta, Finland Posts: 732 Rep Power: 22	Questions: 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?

April 18, 2013, 03:20		#3
vonkam New Member Michal Vonka Join Date: Apr 2013 Posts: 5 Rep Power: 13	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.