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Old   February 8, 2010, 14:35
Default Operating Pressure!
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spk
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Hi guys,

I simulate cavitation in a centrifugal pump. At the exit of the pump i have defined pressure-outlet. At the inlet velocity-inlet. I have set the operating pressure 101325 Pa. I cant understand the significance of the reference pressure location!! Where will i define it??
The point that i defined it, has gauge static pressure 0?

Thanks a lot!!
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Old   February 10, 2010, 05:35
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Jouke de Baar
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Hi, I'm not completely sure but I think the reference pressure will be ignored in your case. I think the reference pressure is only used when you have no pressure boundary conditions (say, velocity_inlet and outflow), in order to keep the overall pressure from floating.

If you do need it, put it in a nicely behaving place, for example avoid being close to the phase-1/phase-2 interface.
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Old   September 16, 2010, 17:36
Unhappy Where is Reference Pressure Location?
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kamal galedarzade
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Hi Jack1980
I want simulate a two stage centrifugal pump, by Fluent. Pump contains: inlet that is a bent pipe, two impellers, diffusers and outlet is a dual volute.There are not pressure-related boundary conditions(e.g., pressure inlet or pressure outlet) in my problem B.C (because I used Velocity-inlet for inlet B.C and Outflow at outlet). Do I enter (X, Y, Z) coordinates for Reference Pressure Location? (for example, the inlet surface center are (-526.5, -271.6, 127.4 ), Do I enter same point for Reference Pressure Location?)
I am confused in the model. Please help me.
Thanks.
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Old   September 19, 2010, 06:50
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Hi kamal_g65,

You have to enter x,y,z at the point where there is atmospheric pressure!


Quote:
Originally Posted by kamal_g65 View Post
Hi Jack1980
I want simulate a two stage centrifugal pump, by Fluent. Pump contains: inlet that is a bent pipe, two impellers, diffusers and outlet is a dual volute.There are not pressure-related boundary conditions(e.g., pressure inlet or pressure outlet) in my problem B.C (because I used Velocity-inlet for inlet B.C and Outflow at outlet). Do I enter (X, Y, Z) coordinates for Reference Pressure Location? (for example, the inlet surface center are (-526.5, -271.6, 127.4 ), Do I enter same point for Reference Pressure Location?)
I am confused in the model. Please help me.
Thanks.
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Old   September 19, 2010, 08:39
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Steven Qhin
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That is right, if you have the pressure boundary condition in your simulation, since you are using the gauge pressure, which means the reference pressure is included already.
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Old   September 20, 2010, 03:07
Unhappy Where is Reference Pressure Location?
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kamal galedarzade
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This is means if relative pressure at inlet equal 700kPa, and i want velocity-inlet define at inlet, i have operate below:
operating pressre= 700+101=801 kPa
Reference Pressure Location = it is same point at inlet surface center ( point: -526.5, -271.6, 127.4 )
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Old   July 28, 2015, 03:28
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Aja
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Quote:
Originally Posted by jack1980 View Post
Hi, I'm not completely sure but I think the reference pressure will be ignored in your case. I think the reference pressure is only used when you have no pressure boundary conditions (say, velocity_inlet and outflow), in order to keep the overall pressure from floating.

If you do need it, put it in a nicely behaving place, for example avoid being close to the phase-1/phase-2 interface.

Hi,

what is your exact meaning of 'floating'?


I am grateful that some one guide me.


Thanks
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