Re: [PSUBS-MAILIST] Re: sub

["Sean T. Stevenson" <ststev@uniserve.com>]

I'd hate to be the one to have to do the stress analysis on a rhombitruncatedicosadodecahedronic pressure hull...

-Sean


On Wed, 8 Aug 2001 08:15:26 -0700 (PDT), Lew Clayman wrote:

>--- "Michael B. Holt" <mholt@richmond.edu> wrote:
>> What was done was a sphere of hexagonal pieces of plexiglas were 
>> assembled into a ball.  One entered the sphere through a
>> door made of the hexagons, and then one walked away across
>> the surface of the water.  So the idea itself is not impossible.
>
>Please provide that link!
>
>The geometry might be a little more involved... something close to a sphere can be achieved with a
>combination of hexagons and pentagons (20 hexes & 12 pents IIRC), look at a soccer ball for an
>example.  A reasonable spheroid can be done with 20 matching triangles, five meeting at each
>corner; slighly less round (but therefore perhaps better for the purpose?) is possible with 12
>pentagons, three meeting at each corner.  This all has to do with the "Platonic solids" if anybody
>cares about the mathematics.
>
>There are (literally) infinite possible variations with two or more flat shapes.  And of course
>faceted near-cigar-shapes and whatnot are possible too.
>
>I wonder, though - if you build a faceted submersible, it seems to me that the pressure on the
>hull will be distributed very unevenly - seams vs middle of facets vs corners etc - could be a
>source of weakness, no?  And many seams equals lots of work, too.
>
>A faceted sub would also seem inefficient in terms of drag, again seams and discontinuities make
>for turbulence and for pressure gradients which might create spurious "lifts" in odd directions,
>making for steering issues as well as for drag.
>
>Or do I miss the point completely (hardly difficult to believe!)
>
>-Lew