Positive Pressure ang negative Pressure

moca · September 16, 2010, 11:21

Hi, dear all

I have modelled external flow around building and I found that there are positive pressure and negative pressure. What's the meaning of the negative pressure and possitive pressure? Is it according with x, y, z direction? or positive pressure for compress and negative pressure for suction, is it right?

Thank's before....

ghorrocks · September 16, 2010, 19:08

Pressures are measured relative to a reference pressure, 1 atmosphere by default.

moca · September 18, 2010, 03:34

Dear Glenn,

Would you like give more explanation about this?

Thank you

ghorrocks · September 18, 2010, 07:00

It is a pretty basic concept and well described in the documentation. Read about reference pressure in CFX help.

September 16, 2010, 11:21	Positive Pressure ang negative Pressure	#1
moca New Member tato Join Date: Jul 2009 Posts: 13 Rep Power: 17	Hi, dear all I have modelled external flow around building and I found that there are positive pressure and negative pressure. What's the meaning of the negative pressure and possitive pressure? Is it according with x, y, z direction? or positive pressure for compress and negative pressure for suction, is it right? Thank's before....

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September 16, 2010, 19:08		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,871 Rep Power: 144	Pressures are measured relative to a reference pressure, 1 atmosphere by default.

September 18, 2010, 03:34		#3
moca New Member tato Join Date: Jul 2009 Posts: 13 Rep Power: 17	Dear Glenn, Would you like give more explanation about this? Thank you

September 18, 2010, 07:00		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,871 Rep Power: 144	It is a pretty basic concept and well described in the documentation. Read about reference pressure in CFX help.