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how to define bc for a oscillating flow output?

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Old   January 24, 2013, 23:55
Default how to define bc for a oscillating flow output?
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Hi,

The output is an oscillating one which has large volumn output and then little volumn reversed flow. I defined the oscillating boundary as 'outflow' but it seems an error as 'reversed flow in 4 faces on outflow 6'.
Could anyone told me which type I should define this bc? Thanks.

Itsqi7
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Old   January 26, 2013, 03:30
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You should use pressure inlet for both outlet and inlet. For more configuration you should use a DEFINE_PROFILE udf.
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Old   January 26, 2013, 04:22
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Quote:
Originally Posted by msaeedsadeghi View Post
You should use pressure inlet for both outlet and inlet. For more configuration you should use a DEFINE_PROFILE udf.
Thanks for ur reply. I'll try that.
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Old   January 27, 2013, 17:37
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Quote:
Originally Posted by msaeedsadeghi View Post
You should use pressure inlet for both outlet and inlet. For more configuration you should use a DEFINE_PROFILE udf.
Hi, Saeed. I tried to use pressure inlet but the warning still happened. I think maybe FLUENT thought there is no fluid beyond the inlet and outlet, so when there is backflow it reports. Can I define, as I suppose, there is infinite fluid at the other sides of inlet and outlet?
My pump structure is as following.
121.JPG
Thanks for ur kind help.

Regards,
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Old   January 28, 2013, 00:35
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It's better to add a channel to inlet and outlet, could get a better results.
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Old   January 28, 2013, 00:39
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Quote:
Originally Posted by msaeedsadeghi View Post
It's better to add a channel to inlet and outlet, could get a better results.
Thanks. By the way, how could I define that channel?
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