Measuring Distance between area of underpressure and overpressure

eRzBeNgEl · May 26, 2011, 06:25

Hi guys

I am handeling with a ContourPlot which shows an area with two pressure Areas...one is under the ambient level, the other one over.

How can I measure the pressure minima tu pressure maxima distance?

The problem is that the underpressure area is on the x-y Surface and the overpressure area is on the x-z Surface

Is there a way to calc this with post?

or do I have to do it on my own

ghorrocks · May 26, 2011, 07:45

The easy manual way is to define some points and manually move them to the right spots and work out the distance between them.

The tricky automatic way is to define two volumes from iso-surfaces which get the high and low pressure regions. Then get the centroid of the volumes (using, for the X direction volumeInt(X)@volume/volume()@volume), then calculating the distance between the centroid points. Pretty easy, but a few steps.

eRzBeNgEl · May 30, 2011, 04:47

Hi,

Thanks for reply...
I tried your suggestion and there is one problem. I cannot create a volume with my Isoclip Area over or above ambient pressure. There is always no Volume defined. The Area itself is given. I use the "From Surface" Option to create the volume

ghorrocks · May 30, 2011, 07:19

Do you have any areas above ambient pressure?

eRzBeNgEl · May 30, 2011, 09:54

Yes, I have, I have got two areas defined...one area under ambient pressure, and the other one over...xx. in m²

ghorrocks · May 30, 2011, 21:20

The approach should work, check for mistakes in your post processing.

May 26, 2011, 07:45		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	The easy manual way is to define some points and manually move them to the right spots and work out the distance between them. The tricky automatic way is to define two volumes from iso-surfaces which get the high and low pressure regions. Then get the centroid of the volumes (using, for the X direction volumeInt(X)@volume/volume()@volume), then calculating the distance between the centroid points. Pretty easy, but a few steps.

May 30, 2011, 04:47		#3
eRzBeNgEl Senior Member Join Date: Dec 2010 Posts: 135 Rep Power: 16	Hi, Thanks for reply... I tried your suggestion and there is one problem. I cannot create a volume with my Isoclip Area over or above ambient pressure. There is always no Volume defined. The Area itself is given. I use the "From Surface" Option to create the volume

May 30, 2011, 07:19		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	Do you have any areas above ambient pressure?

May 30, 2011, 09:54		#5
eRzBeNgEl Senior Member Join Date: Dec 2010 Posts: 135 Rep Power: 16	Yes, I have, I have got two areas defined...one area under ambient pressure, and the other one over...xx. in m²

May 30, 2011, 21:20		#6
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	The approach should work, check for mistakes in your post processing.