would u please help if u have idea how to corect the UDF(turbine inlet velocity) which is already at fluent UDF manul to have parabolic velocity inlet in rectangulr geometry (2D)model thnks in dvnce sihu

The UDF available in the UDF manul is already for a rectangular inlet 2D model issnt it?

yes but when i try to do the countor display the arrow is not wright and also when i plotXY the profile is is have the maximum velocity at the wall of the rectangular and the zero value of velocity at the othor wall so please help how to let it the maximum velocity at the center of the geometry and the minimum value of velocity at the walls(parabolic)profile inlet . thanks much in advance

The udf in manual requires a specific geometry.

- The flow is in direction of the x-axis,

- the centerline of the inlet is at y=0,

- the inlet extends 0.0754m in +/-y .

You can replace the static values with some parameters to adjust the udf. If the center of the inlet is not at y=0 you need an offset in y direction. So if the center of your inlet is at -0.5m the offset would be -0.5 .


#include "udf.h"

#define offset_y 0.0 /* m */
#define extend_y 0.0745 /* m */
#define vmax_x 20.0 /* m/s */

DEFINE_PROFILE(x_velocity,thread,index)
{
real x[ND_ND];real y;
face_t f;
begin_f_loop(f,thread)
{
F_CENTROID(x,f,thread);
y = x[1];
F_PROFILE(f,thread,index) = vmax_x - (y-offset_y)*(y-offset_y)/(extend_y*extend_y)*vmax_x;
}
end_f_loop(f,thread)
}



RoM

thank you very much Rom i solve my problem now, and sory for bathoring you i want to know how to model the mixed convection fluied laminar if i have the avarage density and Cp and K and the viscosity thanks alot siht