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derick August 23, 2005 15:31

Newbie qn
Dear guys:

In my problem, I was trying to input a variable velocity inlet instead of a constant velocity through out. How is this done??

Thanks in advance

Jason August 23, 2005 16:21

Re: Newbie qn
Velocity varying with time or with position?

Varying with time, I think your only option is UDF (or you might be able to stop it after every time step and update the velocity in the BC, but that seems like it would be a LONG way of doing it).

If you're varying with position, then you can use a Profile. It's basically a text file you create that defines different variables with relation to position, and you attach this profile to your BC. Checkout the fluent users manual (chapter 7.26 to be specific) for format and implementation. I'm sure you could accomplish this with a UDF as well.

Hope this helps, and goodluck, Jason

derick August 23, 2005 16:23

Re: Newbie qn
thanks jason...i was meaning velocity varying with position..i will surely look up into the users manual..thanks once again.

Mark Russell August 23, 2005 16:44

Re: Newbie qn
You will find a (spatial) velocity profile UDF example in the Fluent site. I will explore and come back with a better pointer.

edi August 24, 2005 04:06

Re: Newbie qn
In the UDF manual you can find a simple example on how to do it using a DEFINE_PROFILE macro. It's a 2d turbine vane with parabolic inlet velocity profile (3.1.2)

Hope it can help


derick August 24, 2005 11:37

Re: Newbie qn
thanks guys for the help..i will try them.

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