# user subroutine of inlet boundary

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 December 4, 2001, 05:54 user subroutine of inlet boundary #1 raymond Guest   Posts: n/a 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

 December 4, 2001, 12:00 Re: user subroutine of inlet boundary #2 john Guest   Posts: n/a 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).

 December 4, 2001, 22:38 Re: user subroutine of inlet boundary #3 raymond Guest   Posts: n/a Thanks a lot, I mis-understand the process of calling subroutine at first.

 December 5, 2001, 19:54 Re: user subroutine of inlet boundary #4 Ethan Guest   Posts: n/a 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

 December 6, 2001, 06:44 Re: user subroutine of inlet boundary #5 Richard Guest   Posts: n/a 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.