Help for Novel

[Grenouille]

Haha I said that looks like them, not exactly like them! But yeah that makes sense, if they're thick enough, they can protect them

 

[PeterNBiddle]

Those suits would have to made of several centimeters/inches of solid metal, or sci-fi unobtainium material to not be crushed at those depths. Military submarines often have crush depths in the 200-300 meters range... For a spacesuit: think tube of toothpaste under an asphalt roller and you're not far off...

Woven mono molecular nano tubes.

What's so sci-fi about that? : D

 

[kaerius]

Yup, you'd have guys and gals in suits looking like a cross between the Michelin man and a submarine, probably with buoyancy bladders the size of small zeppelins if they want to avoid sinking to the bottom with their suit weighing about a metric ton(or three).

As for the woven nano tubes... they would need to be bonded with another material to be useful, probably in layers, with something like a titanium/aluminum alloy. There are no supermaterials without weaknesses. In this case the strength of the nano tubes only apply when they're a molecule thick... and that's simply not enough.

 

[Grenouille]

Hahahaha! Well there's a really smart inventor in this story, borderline genius, without going scifi I think he's able to build such a suit with a buoyancy bladder smaller than a small zeppelin . But so I don't know why we were discussing the reason they were stuck down there, even with oxygen tanks, they'd be just way too heavy to go back up anyway. Might have to take this story to the Moon instead, should be easier

 

[PeterNBiddle]

Yup, you'd have guys and gals in suits looking like a cross between the Michelin man and a submarine, probably with buoyancy bladders the size of small zeppelins if they want to avoid sinking to the bottom with their suit weighing about a metric ton(or three).

As for the woven nano tubes... they would need to be bonded with another material to be useful, probably in layers, with something like a titanium/aluminum alloy. There are no supermaterials without weaknesses. In this case the strength of the nano tubes only apply when they're a molecule thick... and that's simply not enough.

UHMWPE, ceramic plates and hydraulic liquid that becomes denser with pressure. Plus, of course, the previously mentioned 'tubes. My guess is metals wouldn't cut it at all, the stellar modulus of elasticity that Ti brings to the table notwithstanding.

As we know from free-diving most of the human body does okay with exposure to extreme depth. Maybe a better bet is to significantly obviate the need for a pressure compensating suit by getting rid of excess gas - how about liquid-filled bags that go into the lungs and completely fill them and then feed the lungs single molecules of gas at predetermined doses?

 

[gekodivebali]

Moon would definitely be easier than 1km depth.
Not sure how you would combine 1 atmosphere suits with umbilicals?
The umbilical could be tethered to either the main base or small sub. Think you'd have to invent some scifi material if you want the suit to look close to a human being at all.

 

[kaerius]

Let's say the volume of one of these suits is about 0.2 m^3(spacesuits are about 0.15 m^3), and weight is 1 metric ton. Then they have a negative buoyancy of about 800kg. At 101 atmospheres depth, the least dense gas(hydrogen), has a density about 1/108th of water. You'd need about 808 liters of hydrogen to counteract the negative buoyancy of the suit, at ambient pressure, not counting the material of the bladder, so maybe make it an 850 liter bladder or so, something like a 10 liter scuba tank would be enough to supply the bladder with hydrogen for buoyancy control. (If you choose air for buoyancy instead of hydrogen, multiply the necessary bladder size by 14, or about 11900 liters, I wasn't kidding about the small zeppelin).

---------- Post added May 12th, 2013 at 03:14 PM ----------

UHMWPE, ceramic plates and hydraulic liquid that becomes denser with pressure.

But how does a liquid prevent another liquid from crushing an air pocket? Oh and liquids don't become denser with pressure, liquids are incompressible, well, right up until the point where they become solids(like the metallic hydrogen on the surfaces of gas giants).

 

[Grenouille]

Okay but you guys are hung to the idea of the 1km depth, but it can be much less, this was an old idea but like I said, that can change now. As long as it's too deep for them to get back up on their own...

 

[PeterNBiddle]

But how does a liquid prevent another liquid from crushing an air pocket? Oh and liquids don't become denser with pressure, liquids are incompressible, well, right up until the point where they become solids(like the metallic hydrogen on the surfaces of gas giants).

Right. We need to get rid of the air.

 

[gekodivebali]

The shallower they are, the easier, and exponentially so.