Variable mass flow at boundary
 

Hi fellow Fluent users...

As I'm new to this software, everything feels and is strange.....my newest problem though is that I have a boundary with variable mass flow rate due to changes in area. Can I specify this variation in Fluent or do I have to do it in another way?

Re: Variable mass flow at boundary
 

You can implement it using UDF.

Hi :)

ap

Re: Variable mass flow at boundary
 

Thanks a bunch ap

Re: Variable mass flow at boundary
 

Hi!

Your Udf shoul look something like this (it's an axample from udf fluent documentation - for variable velocity inlet)

/************************************************** ********************

unsteady.c

UDF for specifying a transient velocity profile boundary condition ************************************************** *********************/

#include "udf.h"

DEFINE_PROFILE(unsteady_velocity, thread, position) { face_t f; real t = CURRENT_TIME;

begin_f_loop(f, thread)

{

F_PROFILE(f, thread, position) = 20. + 5.0*sin(10.*t);

} end_f_loop(f, thread) }

regards

MATEUS

Re: Variable mass flow at boundary
 

Don't they have a similar thing for variable mass flux inlet among the udf examples?

Re: Variable mass flow at boundary
 

I wish they had examples to serve all our research problems ! life would be so easy then !

Re: Variable mass flow at boundary
 

You don't say? LOL