Running a UDF only once per timestep

flotus1 · July 5, 2012, 07:00

Is there any possibility to tun a UDF (like DEFINE_SOURCE for example) only ONCE every timestep and not on every iteration?

Daniel Tanner · July 6, 2012, 05:03

Try this:

if ( first_iteration )
{
enter your calculations here
}

I got this from:
http://willem.engen.nl/uni/fluent/do...ips-Tricks.pdf

Let me know how it goes.

akm · July 6, 2012, 08:57

Either what Daniel suggested or you can use the macro EXECUTE_AT_END. Depends on your need, whether you want to execute at beginning or at the end of a time-step.

DEFINE_EXECUTE_AT_END(name)
{
...
}

DEFINE_EXECUTE_AT_END is a general-purpose macro that is executed at the end of an iteration in a steady state run, or at the end of a time step in a transient run.

https://www.sharcnet.ca/Software/Flu...udf/node22.htm

July 5, 2012, 07:00	Running a UDF only once per timestep	#1
flotus1 Super Moderator Alex Join Date: Jun 2012 Location: Germany Posts: 3,427 Rep Power: 49	Is there any possibility to tun a UDF (like DEFINE_SOURCE for example) only ONCE every timestep and not on every iteration?

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July 6, 2012, 05:03		#2
Daniel Tanner Member Daniel Tanner Join Date: Apr 2009 Posts: 54 Rep Power: 18	Try this: if ( first_iteration ) { enter your calculations here } I got this from: http://willem.engen.nl/uni/fluent/do...ips-Tricks.pdf Let me know how it goes.

July 6, 2012, 08:57		#3
akm New Member Join Date: Jan 2010 Location: Netherlands Posts: 28 Rep Power: 16	Either what Daniel suggested or you can use the macro EXECUTE_AT_END. Depends on your need, whether you want to execute at beginning or at the end of a time-step. DEFINE_EXECUTE_AT_END(name) { ... } DEFINE_EXECUTE_AT_END is a general-purpose macro that is executed at the end of an iteration in a steady state run, or at the end of a time step in a transient run. https://www.sharcnet.ca/Software/Flu...udf/node22.htm