[alireza_b]

Hello Dear friends.

I want to simulate flow over a flexible heaving airfoil at low Reynolds number.
I wrote a UDF for that. this UDF works for a rigid airfoil but when I switch to flexible airfoil, there is no motion. Can you help me?
Eq: y=-(constant)*x^2*cos(w*t)

My UDF:
# include "udf.h"

DEFINE_CG_MOTION(airfoil, dt, vel, omega, time, dtime)
{
real z[ND_ND];
real x;
Thread *t;
cell_t c;
face_t f;

begin_f_loop(f,t)
{
F_CENTROID(z,f,t);
x =z[0];
vel[1]=-0.3*x*x*cos(2.0*time);
}
end_f_loop(f,t)
}

Thanks.