# Pressure drop / dissolved oxygen

• fhon
In summary, the author is looking for information on how to calculate the pressure drop when water is pressurized and air is dissolved in it. Henry's law seems to be the answer they are looking for, but they are not sure how to use it.f

#### fhon

Hello Everyone,

I've been trying to find an answer to this but am not getting anywhere. Any help would be greatly appreciated!

I need to be able to calculate (or more likely estimate) the pressure drop I can expect when putting water under pressure if I know there is air in the system.

For example if I have a plumbing system that I pressurize to 100 PSI then removed the pressure source. I know how much water is in the system and can estimate how much air is trapped in sections where I can not purge it. I know the pressure will drop as air is dissolved into the water but at what PSI will it reach equilibrium and no longer dissolve air into the water?

Can anyone help point me in the right direction?