Single 80 redesign?

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Cost aside, there's one very simple reason for the shape of the Aluminum 80. It provides the most efficient mechanical response to containing the considerable pressure involved in storing the air it contains. Other shapes would either require substantial thickening of certain areas or some other expensive solution. Interestingly, Jean-Michel Cousteau's team adopt a different answer to streamlining - feeding air from three smaller (lower profile) tanks to a common regulator...
 
I have a quad 20's rig that I dive with a lot. Slightly less than 18 inches wide, 19 inches tall and 4.5" thick. Weighs about 25 pounds and sure is a lot more comfortable than a single 80.


Now that's a rig that needs pictures! Pics please! :D
 
Interestingly, Jean-Michel Cousteau's team adopt a different answer to streamlining - feeding air from three smaller (lower profile) tanks to a common regulator...

You beat me to it. I think the benefits are probably more from the lower center of gravity than the hydrodynamics but it's cool in any case.

Pete
 
There are probably a number of other things that can be done to lower water resistance. Proper weighting, good trim, streamlined equipment ... but that's going to get us off on a whole new tangent.

Hmm, it's probably cheaper to just buy a scooter than to start thinking about redesigning tanks :D

Edit: These guys look pretty streamlined to me Red Sea Explorers - Scoo-toe-ring
:D:D

Thanks for the video. Now…that looks like a blast. :D
Yeap…just like in the video, get rid of the BC and you get rid of a lot of the drag.
 
Here is a bit more. As was said the ideal pressure vessel is a sphere. This is because the pressure can be equalized in all directions. This is basically what happen when you blow up a round balloon. Manufacturing a sphere is not easy this is because a sphere is a combination of two curved surfaces. A sphere is also not very streamlined relative to the volume it holds.

The next is a right circular cylinder with rounded ends. It is easy to manufacture as there is only one curved surface and is more streamlined in its axial direction. The drawback is that the pressure on the side walls is twice the pressure on the ends.

If a more streamlined cylinder is desired then it would be slightly tapered at both ends. However, this really only pertains to a cylinder moving by itself (i.e. a submarine). Because it attached to a human and a wing any benefits would be over shadowed by the other increases in drag.

Finally as was noted if you want even more streamlining go with small cylinders that sit closer to your body. This reduces your overall profile.

PS Ever wonder why a golf ball has dimples?
 
Hmmm...dimpled wet suit, fins and AL 80 for better boundary layer control...
 
I have a quad 20's rig that I dive with a lot. Slightly less than 18 inches wide, 19 inches tall and 4.5" thick. Weighs about 25 pounds and sure is a lot more comfortable than a single 80.

How about a picture of it.
 
https://www.shearwater.com/products/perdix-ai/

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