[GreyOctober]

Originally Posted by Keelbuster

I thought about that - but since it is driven by the earth's gravitation pull - which is unidirectional, i expect there is a measureable gradient in that direction. It may be omnidirectional as an approximation (a rule of thumb) but wouldn't you expect to see a gradient? What about the sand example - would sand-pressure be omnidirectional? When building a mineshaft they have to support the ceiling more than the walls right? When a mineshaft collapses, the ceiling falls in, I would think.

Now - it may well be easier to build a pressure hull that can stand omnidirectional pressure - (like an eggshell) - building in an assymetry might weaken it overall. Maybs. I'm no engineer though.

Kb

Yes indeed, water has its own weight but due to its molecullar structure the pessure always exerts forces equally, perpendicullar to the surface of the submerged body. As for the sand example: Sand is not a liquid. It might flow but it has different physics. It becomes a fluid and gains fluid properties once mixed with water. As with the forces acting on a body burried in sand for example, the forces are omnidirectional but NOT equal and indeed the greatest force acting would be gravity.
The object with the best pressure tollerance is a sphere. Some of the modern ocean explorers have pressure hulls in form of a sphere. The cillinder has also a very good pressure tollerance and since WWI they had this shape. Remember that pressure difference occurs between a medium (water) and a cavity with a different pressure. There is no presure difference between water and lets say the external hull of the submarine for example.

Originally Posted by jumpy

I should imagine that under the circumstances of sudden and catostrophic implosion, quite a large amount of heat would also be generated in (what was left of) the submarine atmosphere (like you get pumping up a bicycle tire- the pump gets hot) and any crewmembers in said atmosphere would not only be subject to the intense and crushing pressure differential, but a rapid and extreme buildup of heat- a kind of 'compression ignition' of the air in the boat- something which would only last for a fraction of a second, but might actually do it for the crew before them being crushed to death?

I'm guessing some of that is at least possible if not wholely probable in such an event as a submarine implosion... yay discovery channel!

No. Just a big bubble The only heat would be that of the depthcharges.

Originally Posted by Keelbuster

I believe it - burn first, then crush, then drown, then be torn apart by fish. Sweird though - in movies with downed subs (i.e. abyss), the bodies are always intact. Chances are they would be pretty mashed.

Uhm, severe lung collapse,and one that is filled with water, presure equalizes and there nothing more to happen, untill the body gets sniffed out by a shark

Cheers!