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UnSteady Boundary Conditions - Changing with time

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Old   April 11, 2005, 14:03
Default UnSteady Boundary Conditions - Changing with time
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Docker
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I want to simulate an inlet valve in an engine.

Therefore I have a pressure outlet at the valve. The pressure is changing with time, and is defined with a UDF (User-Defined-Function). This works...

However, I want to change the outlet boundary condition to a 'wall' when the valve is closed.

Docker

(I have been using a journal file, but at the moment it is not reading in proporly, if anyone knows the correct order of commands and syntax, for changing boundary conditions at time steps, that would be great!)
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Old   October 9, 2009, 13:49
Smile help me creating a udf for pressure varies with time
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madhu sudhan
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hi i need ur udf file for pressure changing with time.because i have to simulate a flow for a pipe and i have write udf to determine pressure unsteadiness in pipe.
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Old   October 24, 2009, 08:30
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HI , I need ur UDF too.
I'm trying to do UDF about pressure profile.

help me please.

my e-mail :san_36c3@hotmail.com

Last edited by Zenith; October 24, 2009 at 09:38.
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Old   July 13, 2011, 05:06
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Sergiu Stroe
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Quote:
Originally Posted by Zenith View Post
HI , I need ur UDF too.
I'm trying to do UDF about pressure profile.

help me please.

my e-mail :san_36c3@hotmail.com
Hi Zenith,

I need also that UDF file, did you received from the collegues?
can u help me?
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Old   July 14, 2011, 11:01
Default air flow and unsteady boundary conditions
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Nasos
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Hi,


I have to simulate the air flow and calculate the ventilation rate of a building under unsteady conditions. Since the air flow inside the building is dominated by the outside conditions (wind speed, wind velocity and air temperature), how can I solve the problem under unsteady conditions. I have experimental data for outside every 5 min. How can I set these data as boundary conditions?


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