boundary condition

April 1, 2001, 21:03

Hi,

Could anyone tell me how to set the inlet velocity boundary with a variable inflow velocity(ex.the developed flow)? There is only the constant item on the menu.

Thanks a lot!

Lili

April 2, 2001, 06:21

Use UDF

April 2, 2001, 13:42

You have to use a UDF if your BC is very complex, but I hope you like programming in a C based language.

If you just have a time based or periodic profile that does not change as a function of the geometry (IE like in the radial direction) you can use a profile. Define an SI based profile as a function of time, read it from the TUI using the File Read-Transient-Table, then when you go to the Velocity Inlet BC pulldown arrow, you will be able to select your profile rather than the constant.

The Fluent Users Center has more details - get yourself a password if you don't have one already.

John

April 1, 2001, 21:03	boundary condition	#1
Li li Guest Posts: n/a	Hi, Could anyone tell me how to set the inlet velocity boundary with a variable inflow velocity(ex.the developed flow)? There is only the constant item on the menu. Thanks a lot! Lili

April 2, 2001, 06:21	Re: boundary condition	#2
Harry Qiu Guest Posts: n/a	Use UDF

April 2, 2001, 13:42	Re: boundary condition	#3
John Wait Guest Posts: n/a	You have to use a UDF if your BC is very complex, but I hope you like programming in a C based language. If you just have a time based or periodic profile that does not change as a function of the geometry (IE like in the radial direction) you can use a profile. Define an SI based profile as a function of time, read it from the TUI using the File Read-Transient-Table, then when you go to the Velocity Inlet BC pulldown arrow, you will be able to select your profile rather than the constant. The Fluent Users Center has more details - get yourself a password if you don't have one already. John

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