USING IF statement in a UDF for defining Velocity profile at Inlet
 

Hi,

I want to define a velocity profile at my inlet boundary condition. This is my UDF which is working for parabolic velocity, but I want to add a function for y<0.003 and another one for y>0.004, so I need to define and if statement. but UDF does not underestand y in the line (If y<0.003).
How could I define y in my IF statement?
Thanks.


#include "udf.h"
DEFINE_PROFILE(inlet_x_velocity, thread, position)
{

real x[ND_ND];
real y, v;
face_t f;



begin_f_loop(f,thread)
{
F_CENTROID(x, f, thread);
y = x[1];

If (y<0.003)
v= -228.*y+11.6;
else
v=-10200.*y+41.52
F_PROFILE(f, thread, position)=v;
}
end_f_loop(f, thread)

}

Very strange. I can't see any error.

But instead of assigning the value of x[1] to the variable y, you could try using x[1] directly in the if-statement and the equation.

Thank you for your reply,

I tried that before, did not work.

It gave me an error indicating that the undeclared variable in IF statement.
Does it underestand the y variable in If statement?

Hey Amir, I am facing the same problem. My UDF doesn't understand the if statement. How did you fix your problem?