[Sudarshan D Pangavhane]

Kindly help me building a user defined function for following inlet velocity conditions....

"The velocity inlet has a time varying velocity imposed at the start of the solution in the form of a full period sinusoid with an amplitude of 0.05m/s and frequency of 3200Hz. After the sinusoid is complete the velocity remains zero at the inlet for remainder of solution."

[evcelica]

Depends on what software and language you have to use are using:

CFX CEL:
0[m/s] + step((1/3200)-t/1[s])*0.05[m/s]*sin(2*3.14159265*3200*t)

C++:
IF
t <= (1/3200)s
Velocity:=0.05*sin(2*3.14159265*3200*t);
ELSE
Velocity:=0;