[TedBrogan]

hey,

does anyone know where all of the random commands used in udf's by fluent and even some users on here can be found? i'm talking about things that i can't find documented anywhere that seem to be critical for some udf's. for example:

p->stream_index = -1 to turn off a particle stream
loop(I, Ilist) { } to loop through all injections

i cant find documentation on these anywhere. it makes me wonder what other commands are out there that could really help me. can i go through any of the "xxx.h" files to find these?

in particular, im trying to set the start and stop time of an unsteady particle injection in a udf, but i can't find a macro for that in fluent's udf manual. id also like to know where people find these obscure commands so i can help myself more easily in the future.

thanks!

[Bernhard]

Did you check dpm.h in the /src dir of your installation (for me in /opt/packages)? It is nice for accessing information of particles, but you should be very carefull to changes the variables from your udf.

[TedBrogan]

Thank you for the reply, Bernhard.

I did look through all dpm_xxx.h and dpm.h files, and dpm_types.h seems to be the most resourceful file where things like P_INIT_RHO(p) or P_POS(p) are defined. Here's one line of code from the file:

#define P_INIT_RHO(p)((p)->init_state.rho)

To me, that means I could use either the macro P_INIT_RHO(p) or p->init_state.rho in a udf and get the same result. There's nothing defined in this file for start/stop time, however. The deeper question to me is where are things like init_state.rho or state.pos defined in the first place? That file is the one that would probably list all data access variables.

[Bernhard]

I can find the time_of_birth real in the tracked_particle_struct

I'm not exactly sure what time you mean exactly with start/stop time, but I suppose those are solver settings, that you cannot change for a single particle.

[TedBrogan]

I got it now, so here's how it works.

loop(p,I->p_init)
{
I->unsteady_start = ...
I->unsteady_stop = ...
}

You need to have initial values inserted in the GUI other than 0 for both or FLUENT will completely ignore the injection.