# Operating Pressure!

 Register Blogs Members List Search Today's Posts Mark Forums Read

 February 8, 2010, 14:35 Operating Pressure! #1 Member   Join Date: Aug 2009 Posts: 67 Rep Power: 8 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!!

 February 10, 2010, 05:35 #2 Senior Member   Jouke de Baar Join Date: Oct 2009 Posts: 125 Rep Power: 8 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.

 September 16, 2010, 17:36 Where is Reference Pressure Location? #3 New Member   kamal galedarzade Join Date: Jun 2010 Posts: 8 Rep Power: 7 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.

September 19, 2010, 06:50
#4
Member

Join Date: Aug 2009
Posts: 67
Rep Power: 8
Hi kamal_g65,

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

Quote:
 Originally Posted by kamal_g65 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.

 September 19, 2010, 08:39 #5 New Member   Steven Qhin Join Date: Jul 2010 Posts: 15 Rep Power: 7 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.

 September 20, 2010, 03:07 Where is Reference Pressure Location? #6 New Member   kamal galedarzade Join Date: Jun 2010 Posts: 8 Rep Power: 7 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 )

July 28, 2015, 03:28
#7
Senior Member

Aja
Join Date: Nov 2013
Location: Iran
Posts: 216
Rep Power: 5
Quote:
 Originally Posted by jack1980 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

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post manish FLUENT 6 February 25, 2011 05:40 alp FLUENT 1 June 12, 2008 17:24 Andrew Tress Main CFD Forum 1 July 3, 2006 16:00 Antech Main CFD Forum 0 April 25, 2006 02:15 Shankar FLUENT 1 January 30, 2004 05:08

All times are GMT -4. The time now is 04:13.