OT - Science (pressure) question about subs/DCs

[terje439]

Not really belonging in here, but since it is about subs...

Anyway what I am wondering is;
-as a sub dives deeper, the pressure from the water increases.

Does this affect the effect of a DC? Talking IRL here, not IG.

As I see it, there are a few possibilities;
a) no, because the pressure also affects the DC in such a matter that the blast is proportionally smaller
b) no, because the pressure forces the metal in the sub together, hence increasing its blast resistance
c) yes, because the pressure is allready straining the sub so much that it is close to breaking point allready

Or there could be something completely different that is the correct answer
Anyway, just wondering so if anyone knows it would be greatly apreciated!

Terje

[whippleofd]

http://en.wikipedia.org/wiki/Depth_charge

Scroll down to underwater explosions.

Whipple

[steamboateng]

That was an interesting article, whipple.

[oldman45]

That was interesting, thanks.

[terje439]

Indeed. Thank you!

Terje

[Bill Durrant]

Recommended reading .......... puts those ASW attacks in perspective

[AcePylut9]

Anyway what I am wondering is;
-as a sub dives deeper, the pressure from the water increases.

Does this affect the effect of a DC? Talking IRL here, not IG.

With the higher pressure at lower depths, the "explosion radius" of the DC is reduced. 

Should that explosion impact the sub, the sub's depth does matter.  As you go lower, pressure increases on the hull... the difference between the "Sub's Crush Pressure" and the "Water Pressure" is lower than it would be at a higher depth, in other words, your sub's hull is under more stress - and the dc if it hits could be enough to push the pressure "over the edge" and crush the sub's hull.

So it's pick your poison - At lower depths you have a reduce blast radius offset by the less available safety factor in the hull, vs. the opposite when at higher depths.

[NickWright]

There might be a couple of extra things to consider. So, after the DC explosion, there's a bubble of vapour that's oscillating in diameter, which is causing additional damage to the sub's hull, beyond that of the initial explosion. Seems to me that the amplitude of the secondary oscillations would be a factor in how serious the damage is - I'd assume there's only so much movement you can design for in a submarine hull when you build it, before either it, or the things attached to it, fail, become detached, split, get bent out of shape or whatever else. Now, at greater depth, the hydrostatic pressure is obviously higher. The initial "peak" size of the vapour bubble is a function of pressure (because V = ZnRT/P). So at a greater depth, the size of the secondary osciallations is smaller, consequently, the damage associated with oscillation of the hull will likely be lower. Maybe. Although, if you're already so deep that you're below the your "test depth", I doubt that you'd be very keen to expose your sub to any kind of explosion at all, really.

[NickWright]

I ought to refresh the page before I post. Beaten like a red headed step child.


We've arrived at the same conclusion though =)