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Changing boundary condition at pressure outlet using udf

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Old   November 5, 2014, 00:59
Default Changing boundary condition at pressure outlet using udf
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AJK
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Hi, i am doing MTech project in cfd analysis and in need of urgent help.
I am using fluent to solve this problem.
Following is my problem:

1. A simple assemby with 1 inlet and 2 outlets. With a fan near to the inlet.

2. I need to find pressure acting on the blade of the fan, in case one of the outlet is closed.

3. My issue over here is to close and open the output with respect to time.
4. I wanted to know could it be done by UDF.

5. Or any other method which could be used.
I want the change to take place with respect to time.
It would be very kind of you if you could help me out.

Thanks and regards....
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Old   November 5, 2014, 07:20
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Glenn Horrocks
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Yes it can be done by a UDF. But try the Fluent forum if you want to find out how.
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Old   November 5, 2014, 08:07
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Could you provide me with link. I am new to UDF.
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Old   November 5, 2014, 16:03
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#include "udf.h"



DEFINE_PROFILE(unsteady_pressure, thread, position)

{

face_t f;

real t = CURRENT_TIME;



if((t>=5 && t<=10))

{

begin_f_loop(f, thread)

{

F_PROFILE(f, thread, position) = 0;

}

end_f_loop(f, thread)

}

}
Following was the UDF I used but it doesn't seem to affect the fluid flow as pressure outlet is zero. Please anybody could help out.
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Old   November 6, 2014, 01:59
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Quote:
But try the Fluent forum if you want to find out how.
http://www.cfd-online.com/Forums/fluent/
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Old   November 7, 2014, 05:14
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Thank you for the help
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