Titanic tourist sub goes missing sparking search

[Dan]

Easier to just place the rabbit in a 3 ton hydraulic press and see what happens. I don't think it would look much like a rabbit after.

May be the skull would crush, but we are talking about the teeth?

 

[Wookie]

May be the skull would crush, but we are talking about the teeth?

Hit a tooth with a hammer and see how much tooth is left

 

[Dan]

Hit a tooth with a hammer and see how much tooth is left

When you hit a tooth with a hammer, the force applied from one direction. Hydraulic force comes from all directions. That’s why spherical objects are the strongest structures as the force comes from all directions towards a point at the center of the objects. So, pounding it with a hammer is not the same as hydraulic force.

 

[Wookie]

When you hit a tooth with a hammer, the force applied from one direction. Hydraulic force comes from all directions. That’s why spherical objects are the strongest structures as the force comes from all directions towards a point at the center of the objects. So, pounding it with a hammer is not the same as hydraulic force.

Although crushing bodies within a collapsing pressure vessel is more akin to crushing a tooth between a hammer and anvil than just subjecting a body to hydraulic pressure.

 

[BRT]

It would be an interesting test by putting a dead animal skull (road-killed squirrel?) in a carbon fiber cylinder inside a pressure chamber full of water, pressure up the chamber into 6000 PSIg and let the carbon-fiber cylinder imploded and examining the remains. I bet they are till intact.

Maybe, but there is a bunch of energy released and I'm betting on high temperatures.

 

[O-ring]

Is anybody an oral surgeon or work in a dentist's office? Sounds like we need to secure a supply of teeth so we can do some hands on testing.

 

[Wookie]

Maybe, but there is a bunch of energy released and I'm betting on high temperatures.

I’ve seen a calculation that as the air compressed, temps as high as 6000C were calculated. I don’t have the inclination to check the math.

 

[O-ring]

I’ve seen a calculation that as the air compressed, temps as high as 6000C were calculated. I don’t have the inclination to check the math.

That sounds way less fun than pounding on some teeth with a hammer.

 

[Dan]

Another thought comes to mind is some of the implosion energy are being absorbed by the crushing of the carbon-fiber cylinder, so the impact on the objects inside the submersible would be less.

 

[tridacna]

I’ve seen a calculation that as the air compressed, temps as high as 6000C were calculated. I don’t have the inclination to check the math.

(This is not my work)

Modeling the compression of the air in the sub like adiabatic compression:

dU + δW = δQ=0


Treat the air inside the sub as an ideal gas:

δW = PdV


U = αPV = αnRT

dU = d(αPV) = αVdP+αPdV



Substituting into conservation:

dU = -δW

αVdp+αPdV = -PdV


Integrate:

∫-(α+1)pdV = ∫αVdP

ln(P/Po) = -((α+1)/α) ln(V/Vo)

We will write ɣ = ((α+1)/α) then:

(P/Po) = (Vo/V)^(ɣ)


Finally substitute V = nRT/P and Vo = nRTo/Po


Simplify to get:

T = To(P/Po)^((ɣ-1)/ɣ)


ɣ = (5DOF + 2)/5DOF = 1.4 for air

Pressure inside the sub Po ~1atm

Pressure at 13000ft P ~ 400atm

Initial temperature inside the sub To ~273K (Its cold down there)

Plugging in you get... 1500K almost exactly. That's approximately how hot the air inside that sub got for a moment as it collapsed to that pressure.