user subroutine of inlet boundary
 

I have a question about the user soubroutine of inlet boundary conditions. For in my simulation, the inlet value varies with position. For example, the inlet velocity at different location is different and I can define an equation to present the velocity, such as: u(y,z)=f(y,z) I know I can input the value var tablet.But it would take a lot of time, how can it be integrated to the user subroutine in STAR-CD?

Thanks in advance!

Best regard

Raymond YIn

Re: user subroutine of inlet boundary
 

Since your inlet velocity is a fuction of position, then you should be able to do it very easily in BCDEFI. The Boundary positions are passed to BCDEFI (X,Y,Z).

Re: user subroutine of inlet boundary
 

Thanks a lot, I mis-understand the process of calling subroutine at first.

Re: user subroutine of inlet boundary
 

What if the inlet velocity is also a function of time? V=V(x,y,z,t).. since Time is also a variable to be returned , so do you modify BCDEFI or other ways to do it ? Thank you very much ..

-Ethan

Re: user subroutine of inlet boundary
 

The boundary conditions at an inlet can be specified through BCDEFI as a function of position (the variables X, Y and Z indicate this) as well as time (the variable TIME indicates this). The conditions can be a function of lots of other things: have a look at the file "nom.inc" in the ufile subdirectory for a full nomenclature of user subroutines.