[Pmaroul]

Hello all.

Is it possible to initialize some fluid flow properties as functions in terms of geometric location in FLUENT ANSYS?

For example: Rho (x,y)= 2x+3y+100

How can I initialize above expression in Fluent?

Thx in advance for any kind answer.

P.Maroul

[blackmask]

Yes, you can use the following code, which is adapted from the fluent UDF manual.

#include "udf.h"

DEFINE_INIT(my_init_func, d)
{
    cell_t c;
    Thread *t;
    real xc[ND_ND];

    thread_loop_c(t,d)
    {
        begin_c_loop_all(c,t)
        {
            C_CENTROID(xc,c,t);
            C_R(c, t) = 2.0*xc[0] + 3.0*xc[1] + 100;
        }
        end_c_loop_all(c,t)
    }
}

[LuckyTran]

Another way without a udf is to use custom field functions. You cannot apply formulas to primitive fields directly. However, you can create a dummy custom field. Then use the patch feature to patch each primitive variable with this custom field (initialize the fields with anything and overwrite them using the patch). This way you don't need to deal with any udf's.

[Pmaroul]

Excellent.

Thanks a lot for your kind answer.

P.Maroul