“catastrophic implosion”: what this actually means
alright, so we’ve all seen the news, the rich people have died (unsurprisingly)
but some people might be wondering what the fuck “catastrophic implosion” actually means, which is fair because this is how most news networks seem to be describing this at the moment
this is referring to a type of uncontrolled decompression.
uncontrolled decompression can happen in three tiers: explosive, rapid, or slow (which is also mentioned in the wikipedia article linked above)
the speed of catastrophic implosion depends on a lot of different factors.
for example, here is when the Mythbusters tested decompression inside a vintage diving suit
this would be a somewhat slow decompression, at least to start out with.
however, that is a different situation compared to the Titan: it is a suit, not a full diving bell or submersible, and the pressure levels are very different
for those who are unaware of the Byford Dolphin incident, read with caution, but it’s a good case study of a decompression event which occurred on a multi-chambered diving bell
in the Byford Dolphin case, this was explosive/rapid
the Byford Dolphin example is slightly closer to what has happened with the TItan, as far as we know at the moment, but it’s still not the same as the size, pressure level, etc. are still very different-- and there are sure to be more differences that we don’t even know about yet
BUT!! THIS GETS MORE COMPLEX
decompression generally refers to air going out of a thing real fast (think airplane losing interior pressure)
while a compression is more like water crushing a tin can at depth (think submersible)
however, in the case of a diving bell / submersible / submarine, this is still considered a decompression because there is air inside which is squished out by the pressure fuckery that occurs when suddenly the pressure of the water outside is now on the inside, where it surely should not be, and yet, here we are
so this is essentially an explosive decompression resulting in what can only be reasonably described as “becoming a Flubber-like goo fluid with some shards in there, maybe”
at least, as far as we can assume at the moment, based on the currently reported findings.
please keep in mind that I am not an expert by any means, I am just a nerd
but I hope this helps explain what the fuck the news is talking about in regards to the debris field findings thus far in this whole Oceangate debacle
because I can see this being useful too:
Q+A SECTION!
@thefallenangelsgang: “theoretically in an explosive decompression how far would the debris travel? I am bad at math and science and horrified that the submersible might have damaged the titanic further.”
We know that the Titan lost contact with the parent ship around 2 hours into an 8 hour dive. This would suggest that the submersible was not very close to the TItanic, all things considered.
There are plenty of factors to take into any evaluation here, including tidal direction, actual force of debris expulsion from the imploded craft, etc. -- But it’s worth remembering that water creates drag, and likely helped to slow down any debris or shrapnel. Water has a much higher density than air.
So we can’t be 100% sure at this time, but it is likely (based on what we currently know) that any damage to the Titanic itself would be comparatively minimal, if there is any damage at all.
Settled debris may be another story, based on the exact location the submersible was at when the incident occurred. But this is where tidal direction etc. would be important in determining where any debris may have fallen downward to the sea floor, and we don’t yet have that information.
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@omoiintensifies: “So did they explode before the sub explode? Or both happened simultaneously”
Simultaneously, or about as close as possible, at least.
The speed at which implosion occurs is enough (in the particular conditions of this case) to result in a death that is essentially not even registered by the individuals, as the near-instant any “leak” may have occurred, the vessel folded and decompressed so quickly that the human nervous system likely did not have any ability to register it.
Remember that at their depth, they are at several atmospheres of pressure more than what most diving vessels (and divers) are able to typically withstand. That is a lot of pressure.
Imagine that blob fish, how it turns into goo when it comes up to the surface? This is somewhat similar, but in reverse, and way way way faster. Deep sea fish does bad on land, human does similarly bad in deep sea.
What happened here with the submersible was essentially a massive pressure change, occurring in a fraction of a fraction of a second in an immediate one-off crush of pressure (tin can crushing under a hydraulic press), rather than in a gradual process as pressure is slowly changed (such as when a deep sea fish is caught in a net and dragged up).
It is not necessarily that anything “exploded” in the way we think of it on the surface/out of water; The vessel sprung a leak, pressure equalised rapidly (this is the decompression), and this crushed everything and everyone involved at the same time. It’s more of a crushing then an exploding outward, mostly, although of course bits and shrapnel do get all over the place.
A very good example of the math used to sort this out has been provided here, as an illustration of how quickly both vessel and people were gone.
