[GZG] Pressures

2 posts ยท Mar 28 2006 to Mar 28 2006

From: R Campbell-Jones <rcj@d...>

Date: Tue, 28 Mar 2006 08:50:32 +0100

Subject: [GZG] Pressures

Roger Books wrote -

> The biological that live deep in the ocean don't deal with the

> You could inflate a balloon at the deepest spot in the ocean and it

Is it actually that simple?

Presumably, to inflate a balloon at the deepest spot in the ocean you're going
to need an awful lot of pressure to exceed the external pressure to stretch
the balloon until the elasticity of the balloon prevents further expansion..

Conversely, if you inflate a balloon in space you need a lot less pressure,
and there must still be some point at which the balloon is strong enough to
contain the requisite pressure.

After all, the difference between pressure at sea level and that at the bottom
of the oceans is massive, whereas between sea level and space is one
atmosphere.

CJ

From: John Tailby <john_tailby@x...>

Date: Tue, 28 Mar 2006 22:39:41 +1200

Subject: Re: [GZG] Pressures

You can't inflate a balloon at the bottom of the ocean with air that is at the
pressure of the atmosphere at sea level. The balloon won't inflate.

If you inflate the balloon with gas that is slightly higher pressure than the
water pressure then the pressure differential will be contained by the
balloon's skin.

If you try and take a balloon inflated at the bottom of the ocean with high
pressure gas it won't make it to the surface without exploding.

In order to retain the structure of the balloon you would have to adjust its
internal pressure to match that of the water pressure as it goes to the
surface. Most deep diving sea creatures develop similar techniques.

There are some animal forms that look like they might work as spacecraft.
Invertebrates like crabs, are pretty complex shaped creatures and have a

hard shell exterior that could serve as a hull design. You could also use
ideas borrowed from other hard shelled creatures. They could be hulled using a
compound like sea shells. During the life of the ship it could add more shell
and so get bigger as it lasts longer.

Just because the technology is organic based doesn't mean its not been
engineered to contain artificial materials. You would need to be able to

introduce purely artificial compounds to do things that are not found in

nature like FTL travel. Also you need a to introduce hull materials that can
withstand the stresses of re-entry and the drives themselves.

Getting viruses to contain non organic materials like silicon and replicate
could be a first step to producing heat resistant tiles. If you are
manipulating the molecules at that level you could use nano machines to break
bonds and insert new molecules into the strands.

John

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