Single 80 redesign?

[Fish_Whisperer]

Just thinking of our profiles in the water, and how we could streamline and maximize our motion... What if a single 80 were less cylindrical and instead, more like a chair cushion shape? Sort of flat and wide, but curved a little, to conform to the shape of the body?

Does something like this already exist? If not, why not? Is it a bad idea? If so, why?

Pondering...

 

[JBRES1]

I have one word to say why there isn't a tank as described.
COST !!!!!
Jim Breslin

 

[Fish_Whisperer]

Yeah... Still, it makes me wonder if it's possible.

 

[Jimmer]

It's possible, but it's really not the best idea. A sphere is the perfect shape for a pressure vessel, and a cylinder is the next best thing. As soon as you start going away from spherical or cylindrical pressure vessels, you're going to have huge design complications. If you want low profile, you'd be better off with small doubles or triples.

 

[Fish_Whisperer]

Ah... That's what I wanted to know. There are sound physics reasons for cylinders being, well... cylinders! Thanks!

 

[jeckyll]

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

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

 

[DA Aquamaster]

The wall stress would be a lot higher on a non cylindrical tank so a lot more thickness would be required.

The streamlining dea has been approximated by using 2 or 3 thinner high pressure tanks covered with a fairing - the approach behind various designs used by J.Cousteau and JM Cousteau. Forming a single 80 to a similar shape would be mechanically simpler and perhpas not too much heavier, but would not be possible with current tank forming equipment or techniques. It would cost a big $.

 

[oxyhacker]

If you just took an 80 and put in in a press, and flattened it a bit, the weight would stay the same but the capacity would be severely reduced. However, due to the fact that the sidewalls would be flatter now for at least half the circumference, they wouldn't be as strong, so you'd have to either thicken them, which would make the tank heavier, or reduce the pressure rating, which would further reduce capacity. So you would end up with a more streamlined-appearing tank that was as heavy or heavier than it was before, with much less capacity.

Also, flatter configurations, while they may look more streamlined, tend to act like wings, creating negative or positive lift as they move through the water. This can actually increase drag and make the pack harder to swim. The Cousteau shells probably had more to do with creating a unique, easily recognizable, trademark appearance than efficiency.

 

[Scubakevdm]

I think that the problem would be the higher loads put on the flat sections of the tank.

 

[WD8CDH]

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.