Your mix measurement won't change after 3 days with the tank standing, 24 hrs with the tank lying down...l
You're suggesting the orientation of the tank has a significant effect on the time it takes the gas inside to mix?
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Your mix measurement won't change after 3 days with the tank standing, 24 hrs with the tank lying down...l
I suggested that perhaps it was a result of him not calibrating on compressed air, and he dismissed me. Since I don't own an O2 measuring device of my own, I can't really test if this is true or not, but I'm just curious -- does it make a difference like PADI says, or is my instructor correct?
You're suggesting the orientation of the tank has a significant effect on the time it takes the gas inside to mix?
If you want get really wild, you can try to do the same on a set of doubles using the following method:
Empty the doubles, then close the isolator valve between the tanks and add 78 Bar of O2 to the left tank, and fill the left tank with Air to 208Bar. Now fill the right tank with Air to 208Bar. When you're done leave the tanks standing and open the isolator valve. A week later close the isolator valve and check O2 levels on both tanks.
Open the isolator valve and wait a month before you close it again and retest the individual tanks for O2.
I know that we all learned about Brownian motion in high school, and in any gas mixmaster course that we ever took, but I have never been able to get a set of doubles to have the same O2 levels in both tanks after doing the above experiment. Even driving the set of doubles around in a car for a day doesn't help much.
Michael
Thats because even with the Isolator open between the tanks there is such a small area for any gas exchange to go across unless there is an outside force to push gas from one tank into the other there is no flow to do the mixing.
Thats why I always supervised whenever someone was filling my doubles, too many shops around here dont see enough doubles to figure out the isolator.
Use a better analyzer.
Shaking a tank of gas has no effect on how the molecules mix. Gas molecules move very fast. Any gas mix is effectively mixed, with the cylinder just sitting, rather quickly.
Shaking a tank of gas has no effect on how the molecules mix. Gas molecules move very fast. Any gas mix is effectively mixed, with the cylinder just sitting, rather quickly. Although it would be rather amusing if you could get some video of your instructor shaking his scuba cylinders to mix the gas. Sounds like the kind of prank an instructor would play on his DM candidates.
Unfortunately, people tend to want to understand new things by trying to relate them to other things they already understand. Two liquids in a jar, like salad dressing, can separate due to their different densities (and the fact they are liquids.) And you can see them mix when you shake the jar.
But gases are different. Because they are not liquids.