Mixing gases in a cylinder for a partial fill

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

When the fill is complete, and the whip is still connected, crack the valve on the air and give the tanks a quick blast before disconnecting. Mixes everything nicely.
 
When I first got into diving I asked Edd Sorenson who was filling my tanks if the gases would separate if they stayed in the tanks too long. I am sure he got a laugh later out of that.
 
Well I am glad I asked ...

How come the movement from the fill is not enough to start mixing the gases ?
Best answer to that I think is gas at 200bar behaves differently than gas at 1 bar
 
When I first got into diving I asked Edd Sorenson who was filling my tanks if the gases would separate if they stayed in the tanks too long. I am sure he got a laugh later out of that.
I don’t think it’s a stupid question.
 
I don’t think it’s a stupid question.
Stupid question or not, I'll ask it here, because I don't know: Do gases separate in tanks after awhile?
 
Stupid question or not, I'll ask it here, because I don't know: Do gases separate in tanks after awhile?
I do not know under 200bar pressure and in a cylinder but I know that gases won’t separate at 1ATA in our atmosphere.
 
Is it because there is too much entropy even in a tank compared to the relative densities ?
Interesting concept, although I would have thought that thermodynamics would cease to factor once the gases had stabilised. However, I'm not a physicist so take my opinion with a pinch of salt.
 
I know when an entonox (laughing gas) cylinder sits in the cold it separates, not sure about the science.
 
https://www.shearwater.com/products/perdix-ai/

Back
Top Bottom