[anthonyczy]

Hi
I am new to FLUENT and writing UDFs. Please help me out.

I would like to write a UDF for the inlet velocity profile of a pulsed fluidized bed. The pulses are 1Hz, with amplitude 0.1 m/s.
0 to 0.5 seconds, 0.1m/s
0.5 to 1.0 seconds, 0 m/s
1.0 to 1.5 seconds, 0.1m/s
and so on till 300 seconds

Thanks!

PS I have a template here but i do not know how to describe the equation of this square waveform.

#include "udf.h"
DEFINE_PROFILE(unsteady_velocity_profile, t, i)
{
real current_time;
real x[ND_ND];
real y;
face_t f;
current_time = CURRENT_TIME;
begin_f_loop(f, t)
{
F_CENTROID(x,f,t);
y = x[1];
if (current_time < ______ )
{
F_PROFILE(f,t,i)=______;
}
else
{
F_PROFILE(f,t,i)=0;
}
}
end_f_loop(f, t)
}