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Old   July 29, 2012, 08:18
Default UDF not working
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Daniel Ortega
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I am using a UDF for inlet velocity boundary(vx=2*y).when I interpret my UDF it doesn't show any error.But after selecting my UDF in B.C. when I want to initialize, it shows a constant velocity value. Is there anyone who knows what the problem is?
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Old   July 30, 2012, 03:03
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Alex
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Unless you show us the UDF you used, you will have to wait for a psychic with basic knowledge in UDF programming.
I can tell you that these people are quite rare
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Old   July 30, 2012, 12:02
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'Initialize' provides an initial solution over the entire domain. Through the Fluent GUI you can give only a single initial value for the entire domain. If you want the initial solution to be of the form Vx=2y, you will have to write an initialization macro (DEFINE_INIT).

However, im guessing you have written a udf for inlet B.C. (DEFINE_PROFILE), which will be used as the inlet velocity condition for obtaining the solution.

The initial solution is given to the solver as a starting point for the calculation, and should not affect the final solution (unless, of course, it is way off which will lead to a divergence).
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Old   July 30, 2012, 12:05
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Quote:
Originally Posted by flotus1 View Post
Unless you show us the UDF you used, you will have to wait for a psychic with basic knowledge in UDF programming.
I can tell you that these people are quite rare
@Alex.. yes, people like me are rare hahaa
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Old   July 30, 2012, 16:37
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thank you guys! yes I used (define_profile) for my inlet velocity. In fact the problem was due to the written code. I guess after this project I'll be more psychic than before
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