Hi how can i define vilocity according bellow: v=sinat v: vilocity t:time a :constant parameter i want udf program whit c code. please help me .i need your help.

Hi,

Refer to the Fluent user Manual, they have given examples with the codes.

Aravind

#include "udf.h" DEFINE_PROFILE(unsteady_velocity, thread, position) { face_t f; real a,t = CURRENT_TIME; a=10.0;/*change to your value*/ begin_f_loop(f, thread) { F_PROFILE(f, thread, position) = sin(a*t); } end_f_loop(f, thread) }