UDF Wall slip velocity
 

Hello,


I'm new at the forum and with UDF topic. I'm trying to set a slip velocity at the wall defined by the next function


u= beta* du/dn, n being the normal vector to the wall


As a first trying I want to solve the problem in a 2D case (flow between two plates) so the equation is u= beta* du/dy, at the wall.

I wrote this code but it send me a problem and then fluent is closed.

My code is the next one


#include"udf.h"
DEFINE_PROFILE(mass_fraction_profile, t, i)
{
real x[ND_ND];
real z;
face_t f;

begin_f_loop(f,t)
{
F_CENTROID(x, f, t);
z=x[1];
F_PROFILE(f,t,i)= C_DUDZ(F_C0(f,t),t)*0.01;
}
end_f_loop(f,t)
}


Any suggest is welcome!

Hi again,
Please, any help is appreciated!

fluent has build in slip function, you don;t need to write UDF

best regards