Banner Ad 1

Volume/Pressure calculations

Place for general submarine conversation

Postby ThierryC » Mon Mar 03, 2003 2:33 am

I am trying to determine the size of the air reserve tank for my sub. My ballast tank will be about 4L, what size should the air tank be at a pressure of 100psi, 150psi and 200 psi
And what is the formula that would allow me to calculate this ?
Thanks
There are 10 kind of people, those who undertand binary and those who don't !
Sub-Systems
User avatar
ThierryC
Registered User
 
Posts: 176
Joined: Fri Feb 21, 2003 3:52 am
Location: Perpignan, France

Postby 115-1045840519 » Mon Mar 03, 2003 2:59 pm

atmospheric air pressure at sea level is 14.7psia. So if you compress 4L of air to 100psia then the volume of the air tank would need to be under 13% or rougly 1/2L. The formula is:

Vt = Vo * (P + 14.7) / 14.7

where
Vo = ballast tank volume.
Vt = compressed air tank volume.
P = pressure of compressed air in psi.

This is idea so you'll want to add some safety margin. Maybe 10%. If you are trying to make a ballast back up, you don't necessarily need to vent the entire ballast tank. Naturally if your trying to overcome a leak in the ballast tank then you'll need more air.

Jerome
115-1045840519
 

Postby 115-1045840519 » Mon Mar 03, 2003 3:03 pm

So little to see and so much time...........

scratch that..............

The formula should have been

Vt = (Vo * 14.7) / (P + 14.7)

And for those nit-picking, yes I earlier stated a compressed air pressure of 100psia in my example. It should have been 100psi.

Jerome
115-1045840519
 

Postby ThierryC » Mon Mar 03, 2003 4:37 pm

Thank you very much, that is exactly what I needed !
There are 10 kind of people, those who undertand binary and those who don't !
Sub-Systems
User avatar
ThierryC
Registered User
 
Posts: 176
Joined: Fri Feb 21, 2003 3:52 am
Location: Perpignan, France


Return to General

Who is online

Users browsing this forum: redboat219