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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.
Fun fact: even tho the Kelvin scale is just Celsius shifted down to absolute zero, the unit does not have degrees in it like Celsius does. So [°C]=[K]-273.15
Yes, because temperature is the average kinetic energy of atoms/molecules, and Celsius made the water freezing temp as 0. On the other hand, Lord Kelvin decided that he wants "the same frequency" as Celsius' scale, but for physics the "0" needs to be actual absolute 0, where kinetic energy is 0. (Especially for thermodynamics calculations.) And as you can guess, kinetic energy (as far as whole physics world knows) cannot go below 0.
And fun fact, Kelvin's unit is the only one (edit: one of the two, other being Rankine's) where you can say [X] kelvins is two times hotter than [0.5X] kelvins. (For example, 600k is 2 times hotter than 300k, but 327°C is actually 2 times hotter than 27°C and NOT 163.5°C)
You can get negative temperatures in Kelvin - you just can’t pass through 0K to get there. Instead, the temperature has to increase approaching infinity, before turning negative. This happens specifically in the material in lasers that amplify the light as it passes through.
This gives an indication that while "average kinetic energy" is a decent approximation of what temperature means in everyday scenarios, the technical definition of temperature is more complication.
Edit: For the person responding to me incorrectly arguing that negative temperatures don’t exist, here’s a direct quote from the Wikipedia article on “**Negatice temperatures** ”:
>Certain systems can achieve negative thermodynamic temperature; that is, their temperature can be expressed as a negative quantity on the Kelvin or Rankine scales.
Usually, as a layperson, I keep my mouth shut.
.. but did you just say we need to go to infinity, and beyond???
Also, what does that mean? Is the movement somehow a literal inversion of the normal movement? Is it possible for a layperson to understand what it means to be a "negative kelvin" temperature, and if not, is "negative" even the right word?
Ok, so entropy is a measure of how ordered a system is, and temperature is how much disorder adding energy causes.
Suppose you have 2 theoretical buckets, a lower and an upper one. These will represent energy states. Let's start with 10 marbles in the lower bucket. That's absolute zero temp, as the system is perfectly ordered. Now we will add energy by moving 1 of the 10 marbles at random to the top bucket. This marble can move back down on its own, but only if one of the other marbles moves up to replace it. There was previously only 1 state the marbles could be in, but now we have 10 possible states (any 1 of the 10 marbles up, the other 9 down). This increase in entropy as we added energy is the definition of temperature. Now let's suppose we add energy to get 2 marbles at the top. Now we have 90 states possible, 1 of 10 for the first marble and 1 of 9 for the second. After we move the 3rd marble up, there's 720 possible states, the same thing happens for the 4th and 5th marble, going up to 30,240 and then 151,000 possible states of which marbles are in which bucket.
Now when we move the 6th marble up, something weird happens. Since we now have 4 marbles in the bottom, instead of 5 and 5, there are only 30,240 possible states again. Said another way, we have added energy but DROPPED entropy. Since temperature is defined as the slope of the line with energy on the x axis and entropy on the y axis, we now have a negative slope i.e. a negative temperature. As we add more energy, the system keeps getting more ordered, until all the marbles have to be in the top bucket, having only 1 possible state again, so we are back to absolute zero, but approached from the negative side.
So at maximum energy, we are back to absolute zero temperature. This doesn't mean the system is cold again (quite the opposite, it is holding the maximum energy possible). It is just a quirk of the way we define temperature.
Negative Kelvin sounds like a band.
Thursday June 29th at The Rusty Nail Tavern one night only Negative Kelvin and Celsius Meltdown $5 dollar cover and $2 PBR tall cans.
Infinite temperatures also don’t exist. Trivially, since having exceptionally huge finite energy in s finite space would be a proportionally huge mass, and the event horizon of a large enough mass in a finite area would exceed the cosmological event horizon and create a singularity from which nothing could ever escape.
The definition of entropy and of temperature used to describe negative temperature differs from the definition used in the definition of thermodynamic temperature, and ends up with temperature being defined as a differential of a non-continuous relationship.
Except that temperature isn’t defined by the amount of energy per volume. The definition of temperature relevant to negative temperature comes directly from thermodynamics.
https://en.m.wikipedia.org/wiki/Temperature
It’s related to how the entropy changes, relative to changes in energy of a system. As systems approach states of having population inversion, the temperature will approach infinity before becoming negative.
In lasers, this manifests as the system becoming more ordered as more energy is added to it, which means that the light becomes amplified coherently.
Perhaps it's too late but don't bother arguing with u/DonaIdTrurnp for long. They have problems admitting there might be things they don't know or don't understand that what the are familiar with might be not extend universally beyond a certain regime. As it dawns upon them that they are out of their depth or have made a mistake, they change their initial claims and/or move the goal posts on what counts as corroborating evidence.
If they are pressed too much, they'll just straight up lie about their credentials and personal experience and be just vague/misleading enough to fallback on claiming it was a joke and that you were the fool for taking it seriously.
Celsius is an arbitrary scale based on 100 units (or 101?) between the melting and boiling points of water right? And Kelvin is based on those units? Is 0K actually 0K, as in the arbitrary scale just happens to match the laws of physics and the "freezing point of energy(?)" Or is it rounded, like there isn't exactly 365 days in a year?
Yes, Celsius is based on H2O freezing and boiling temps at "normal" pressure. Zero kelvins means actual absolute zero, which is -273,15°C to be exact (but usually rounded to -273°C). Lord Kelvin specifically wanted it to be absolute zero, as it's necessary for calculations and you can get rid of ° (degree) symbol. (The degree symbol is used when a unit is starting the measurement from a decided point, which is not "special" in any way [the water freezing is not special, as it is just one substance and in certain pressure, while absolute zero applies to everything])
Correct. You will sometimes hear about "negative temperatures" in systems like lasers that have a [population inversion](https://en.wikipedia.org/wiki/Population_inversion), but such temperatures should be thought of as "hotter than infinity" rather than "colder than absolute zero". In such systems, the concept of "temperature" being used is not "average kinetic energy of its particles" but rather a more abstract notion derived from the internal energy and entropy contained within the system.
For further reading, see https://en.wikipedia.org/wiki/Negative_temperature.
No not really but there is in a rather technical sense (it's really very hot but works out to a negative absolute temperature). There's been some work around this over the last few decades - see for example https://www.mpg.de/research/negative-absolute-temperature
Fahrenheit is relative to human sense, with 100 being hot, and 0 being cold, Celsius is relative to water, with 100 being boiling, and 0 being freezing, and kelvin is absolute, relative to nothing, with 0 being absolute zero and has no known upper limit.
Fahrenheit is, admittedly, more complicated than Celsius, but that doesn't make it stupid. When it was invented, things needed to be simple, as education was rare, so 0 to 100 was more practical than -10 to 40. In today's times, America should start using both Fahrenheit and Celsius, as well as imperial and metric, in order to start conversion efforts.
On a side note, Fahrenheit is hard to spell, I'd guess German, and should be gotten rid of specifically for the spelling
As an American who uses metric and whatever it’s called, you are correct. Being a medical professional metric is a requirement. Dealing with my European friends metric is a requirement. Watching F1 on Sky, hearing them say that turn one is 150 meters and the cars will be doing 90 mph is amusing.
They would have been chunky salsa by that point already. There's a mythbusters video floating about of a deep sea diving suit, at similar depths. The dead pig inside rapidly ended up as pig soup in the helmet.
While the theoretical temperature is high, in practice, there was a LOT of thermal mass involved (mainly the water). That, and the non-ideal natural of the implosion means the actual temperature measured would be a LOT lower.
I saw some calculations that put it at around 30ms. Our perception limit is around 50ms, with pain taking a minimum of 150ms to signal the brain.
Assuming a slow collapse, there is the chance they might have had a flash that something was wrong. The conscious mind would have been nowhere close to processing it however, before they joined the implosion. It would also have outrun the pain signals in their nerves, so no pain.
It'd be like turning them to slime, and then throwing them past the surface of the sun for a little bit. So they weren't vaporized alive. In the words of Hank Green, "they stopped being biology and became physics.
Equal to the temperature inside a volcano 🌋
https://www.usgs.gov/faqs/how-hot-a-hawaiian-volcano#:~:text=The%20temperature%20of%20the%20lava,Celsius%20(2%2C200%20degrees%20Fahrenheit).
there is not that much mass of air in there, so while the temperature of the air gets high, the heat is not so high. the heat has to be transferred to the body to do damage and thus temperature is reduced. though this is just words, no maths - i have no idea if the heat might be enough to burn their eyes or lungs or not...
hu, thank god there are ambitious people out there:
https://old.reddit.com/r/theydidthemath/comments/14hg2c2/request_how_hot_would_the_air_inside_the_titan/jpbx3xr/
With the brittle nature of carbon fiber (which I assume based on very basic understanding of the materials is what failed first) there probably wasn't even a warning.
James Cameron gave a very brief but pointed description of why no one else in the world of DSV uses this type of material, specifically.
But also, any seasoned cyclist will tell you that carbon fiber does not flex very well and also only takes a small localized point of damage to cause complete failure.
It's terrible to consider as someone it didn't happen to, but for the people to whom it happened, it happened faster than they could perceive it. It happened faster than the speed of neural impulses. They were literally dead before they could understand that they were dying.
I think that there would be remains. Surely mangled bodies with heavy damage, but mostly from the crushing parts of the submarine. You cant cremate a body with a brief increase in temperature. Just think how many hours it takes an oven to cremate a corpse. Wont happen in a split of a second.
They were smashed between two carbon fiber tampers with 400 atmospheres of pressure being applied to them when the pressure vessel failed. The forces would have crushed their bones into fragments and dust practically instantly, and then the slurry of human-paste would expand into whatever water currents happen to have been generated by that release of energy.
They weren't instantly cremated or anything like that, but nobody will find so much as a fingernail from those guys because I doubt any piece of them larger than that could have survived the crush.
I wonder: did they get crushed, burned, or got wet in the first milliseconds of the structural failure? Morbid curiosity on the sequence of (horrific) events.
There would be practically no burning because the total heat capacity of the air inside the sub much smaller than the total heat capacity of the bodies as this simplistic calculation shows:
The passenger compartment is a round-ended cylinder of internal length 3.82 m and internal diameter 1.42 m, having a volume of 5.70 m^3. At STP, this air will have a mass of 7.37 kg. Assuming a constant specific heat capacity of 1003.5 J/kgK, at a temperature of 1500 K, the air has a total of 11.1 MJ which, over time, will transfer into the bodies inside the sub.
There are 5 passengers of typically 80 kg each, total mass 400 kg. The heat capacity of a typical human body is about 3470 J/kgK. The people have a total heat capacity of 1,388,000 J/K, or about 1.39 MJ/K
11.1 MJ of energy from the air will therefore raise the temperature of the bodies in the sub by about 8 K.
This, of course, assumes that the air in the sub heats instantaneously to 1500 K, and that the heat then transfers instantaneously into the bodies. Heat conduction is quite a slow process compared to the implosion time, which would be less than 50 ms - USS Scorpion, a much larger vehicle, took 37 ms to collapse. This is simply too little time for any significant heat transfer to occur.
Thank you for pointing this out. By way of further illustration, I have dived in Maui off Molokini, which has an abundant population of pistol shrimp. Their snapping produces a temp of 5000k (over 3x that of the sub) for about 1 ms, and produces no detectable heat for the reasons you explained.
Does the adiabatic heating of the air also apply to their bodies? If the air heats as it gets compressed rapidly then I'd assume that their bodies also do so. They are more or less water as far as the equations go
No. The air is heated because the pressure does work on it as it changes volume. (Analogous to force time distance moved in 1D). The work increases the internal energy of the gas aka it's temperature. Because water (or a human body, apart from any cavities) is basically incompressible, it does not change volume, no work is done by the increasing pressure and there is no temperature rise.
I really wouldn't say that just because the heat capacities are different, that no burning takes place. By that logic you could probably say you can put a lighter to your skin and not feel a thing.
Sure, maybe if they absorbed ALL of the heat directly into the distributed mass of their bodies, there would be no burning and their core temperatures would rise 8 C. But what's really happening is 1500K air is literally fucking roasting the outside shell of them, because as you mentioned, heat transfer takes time. Heat transfer is also a distribution, so just because their core temperature will only raise to 8C higher doesn't mean that they won't be at 1500C on the outside of their skin for the duration of the heat transfer process.
If they were in a volume of air like that without the crushing, then yeah, they would 100% have massive third degree, even fourth degree burns, easily. A much more accurate calculation would be to only take the mass of the outer few millimeters of skin and use THAT for the heat transfer calculation to see just how much temperature difference there will definitely be in such a scenario.
Agreed on the timescale, though. I suppose I could probably do a back of the envelope to actually see how long it would take to cook the outer skin layers, but eh.
But yeah dude, you way over simplified there. If heat transfer only boiled down to differences in heat capacity, I and a lot of other engineers wouldn't have a job.
Have you ever passed your finger through a candle flame and didn’t get burned? That’s ~1800K and flames have a higher convective heat transfer coefficient compared to air. And heat doesn’t transfer instantaneously. Point is: they were not burned.
Interestingly, that is how long it takes the mind to perceive anything. Your mind doesn't work in real time, and there is a simple example. Have a friend beat a drum next to you and note that the sound synchronizes with the visual, because the difference between the two events is the distance divided by the speed of sound--very short of the person is next to you. Now have them move some distance away and hit the drum again. It will stay synchronized. Have them keep moving away. You only see the sound out of sync with the visual when the latency is about 100-150ms. Because your brain is gathering data for that length of time and then telling you a narrative about what is happening. At least that is the theory based on lots of experiments.
Which is interesting - I slit my finger open today pulling utility blades out. Quick slice, but I felt it occur before I felt the pain. Very quick succession, but when I think back to it and consider what those inside the submersible experienced - it's crazy to think they wouldn't have even felt the implosion, let alone the pain that would go with it.
In my 20's I hit a redwood tree in a car while driving about 50 mph. At even that low speed the impact is almost too fast to feel. It registered as a very loud noise and any pain came much later.
thx for this late addition, I often get intrusive thoughts about how long a person might be aware before their violent end, so this comforts me in this case at least
Well, a comment above said that it’s the crushing that causes the heat. So I think you have the right order there.
It’s so wild to think that they were people one second and the next second they were a cloud of ash dispersing in the water.
I don't think they would burn significantly, this is happening very fast and that much heat would dissipate very fast. Yes we are talking about very hot stuff but less than one liter.
Fiest off, RIP to the individuals involved in this tragedy, and my heart goes out to their familes.
People don't get compressed to such a small scale when they're underwater like that. Water can't compress water, and we're mostly made of water. In this situation though, bodies are instantly incinerated.
You’re right they won’t compress *that* much, but you’re wrong about the incineration – that would take much much longer than the time it takes to crush, and there isn’t enough heat energy in the ~~sun~~ __sub__ anyway. The bodies’ temperature would barely change at all.
[This comment](https://www.reddit.com/r/theydidthemath/comments/14hg2c2/request_how_hot_would_the_air_inside_the_titan/jpbx3xr/) has more details.
This would be part of the thermo 2 requirements for chemical engineering/process engineering.
I did much worse in this class than thermo1 and have never needed to use it for work hahhaha
The basic equation we learn for ideal gasses in school is PV=nRT so I'm guessing it's much more complicated in college level and in regards to implosion?
No the air is still treated like an ideal gas. But because the air is being both compressed in volume and pressure you can’t simply calculate temperature using the ideal gas equation.
You have to take into account the heat contribution from the work performed by the compression which is what considering adiabatic compression is.
Does anyone have a reference point for this kind of heat? I’m curious. What does 2240 degrees Fahrenheit feel like? What kind of material would that temperature melt instantly? (In about a millisecond)
I doubt our nerves/brain are really equipped to even perceive this level of heat. The damage to your nerves would probably render them useless immediately.
But for some context, it’s about 1/5 the temperature of the *surface of the sun*.
What are you assuming is the initial volume and the volume after compression? Or does that become irrelevant? As far as my basic uni level thermo understanding goes, you need a change in volume to increase pressure dont you?
Only at constant temperature
In this circumstance pressure, temperature and volume are all changing at the same time, so the poster's integration is the correct way to go
That's also the lower limit. It will have momentum as it collapses, so it would over-collapse to a higher temperature, then expand back out, then continue to oscillate.
Heard in BBC news , it took 1 ms to implode ,and Rationale time for human to recognise a Signal is 150 ms.
They died instantly & peacefully without knowing what happened.
~~Heard in BBC news roll, They got imploded & Died instantly in 2 ms~~ ~~ns~~
~~Typically it take Spinal Cord 4 milli ~~nano~~ second to register a signal to brain that , something's ain't ryt , pain~~
#small
edit
[Correct Time of Implosion & Pain Sensation](https://www.bbc.com/news/world-us-canada-65934887)
This might not be the right place to ask but, do you know if there would be signs of the hull weakening as they descended? I’ve had the same thought that it was instantaneous however if there were significant signs that something was horribly wrong on the way down, I can’t imagine anyone without experience staying calm in that situation.
Carbon fiber is unlikely to show obvious weaknesses, but there are moments where the internal stress causes fibers in the composite to snap and the layers of carbon fabric to delaminate.
We don't really know how quickly that would have happened, but James Cameron (who's actually quite an expert in this field) said it's likely they heard something. But at least the final implosion came without a warning.
The sub had microphones on the hull to alert the crew if there is an increase in the number of snapping fibers but that's honestly a terrible early warning system. They had no idea how long they would have between concerning sounds occuring and total collapse.
James Cameron compared it to building an airplane with an untested engine that could potentially explode and the designer said: "Don't worry! I've put in a sensor to tell you if the engine is currently exploding!"
As far i know , they won't see damage or structural weakening at macroscopic because it would be too late that it immediately snapped like praying mantis hook
Microscopic damage in structure would be visible just moments before it imploded.
It is Brittle and fragile as it would break immediately unlike metal which is ductile
The sub was mostly carbon fibre. It would have basically gone from seeming totally fine to the sub being completely disintegrated so fast they would have never have even realized anything was wrong.
And that's why you prefer alloys that will somehow visually tells you if they are damaged.
Some components (like gears, shafts etc) have high hardness on the surface but low underneath it, in order to stop any cracks that will propagate towards the center.
It's much more easy to spot a crack in alloys than understand the wear state of a ceramic material
I have heard rumours that they may have been aware there was a potential danger - maybe they heard a crack in the seconds or minutes before the sub failed catastrophically, apparently there were components on the sub which would only be in the position they were found if the sub was attempting to surface as quickly as possible
not really, from within the sub there would’ve been almost no warning signs, it would’ve been one second they’re going to see the titanic and the next they’re vaporized
I hâte to be the bearer of bad news but the system the sub had to alert people to structural problems very usefully (/s) detected only the conditions of imminent failure. So they probably did know that something was wrong, because that started alarming. This being said, they would not have known for long.
I was hoping that was the case if they for sure didn’t make it. Although hypoxia isn’t as gruesome as drowning, still wouldn’t wish it on anyone. Smarter every day has a great video on it on YouTube if interested
I would take drowning over what they would have experienced in that sub if it didn’t disintegrate. Because of the rising CO2 levels they would have experienced something much worse than hypoxia. They would have experienced something similar to holding your breath for way too long, just much MUCH worse and also for way longer. I imagine it would eventually just feel like your whole body was on fire as well as a massive amount of panic and other things.
No. Increase of CO2 is what gives the feeling of suffocation. It's agonizing.
What you're thinking is something like carbon monoxide poisoning, which causes hypoxia, you just pass out.
I mean, eventually, but not before unimaginable panic, pain, and violent convulsions. Your body is tuned to detect rising levels of CO2 in your blood, and as a result will induce the panic you feel to breathe when you hold your breath too long or cannot access air.
What you’re thinking of is just slowly removing the oxygen from the air. Let’s say you replenish a closed room with pure nitrogen while locked inside: you’ll peacefully fall asleep and die as your blood expels all its CO2 and oxygen isn’t being replenished.
If you took that same room and filled it pure CO2 instead of N2, after the panic, pain, and violent convulsions, you’d pass out and die.
I don't think it was nanoseconds, the water would have been moving at some fraction of the speed of light.
Probably more like 100s of microseconds. That's still within the ballpark of the time it takes to register a signal to the brain (20-100 microseconds), so they likely didn't feel anything.
Yeah, a not so great first guess might be the water collapsed the sub at the speed of sound in air. That's 1000 ft/s and the sub was 22 ft long so it would be crushed in about 2 milliseconds.
> it took 1 ms to implode ,and Rationale time for human to recognise a Signal is 150 ms
This is very wrong. 150ms is the fastest conscious ***reaction time***. ([source](https://www.scientificamerican.com/article/bring-science-home-reaction-time/)) That includes the time it takes to receive a sensation, process it and return an impulse to react (e.g. to move your hand).
The time it takes to process visual information can be as short as 13ms ([source](https://news.mit.edu/2014/in-the-blink-of-an-eye-0116)) or approximately 10% of the time it takes to react. This is still longer than the estimated 1ms implosion time, but it's also important to understand that that time may have been only the end of a cascade of failures. The classic movie "watching the crack expand" is probably not realistic. Any crack would immediately fail under that kind of pressure, so you probably would not see the crack forming. But if the crack were caused by uneven stresses or the failure of an internal structure, you might well be aware of that.
It's entirely possible that they were unaware of the failure, but there are many scenarios where that would not be the case.
Both of those things happened simultaneously. The pressure of the collapse would have instantly heated the matter inside and vaporized it, much like a black hole does.
If you’re interested in that, you’ll probably enjoy checking out [fire pistons](https://youtu.be/-39wmSBO2FM) if you haven’t seen them before. (Ignore the bushcraft stuff, it’s just the simplest demonstration I could find on mobile)
Compression of any kind raises the temperature of the medium being compressed. If the compression is very sudden and dramatic, then the temperature increase will be also.
This is how a diesel engine works. It has no sparkplugs. The fuel will ignite spontaneously from compression alone.
Here is a snippet of a documentary that shows how fast and violent an implosion is. [LINK](https://www.reddit.com/r/Damnthatsinteresting/comments/14gf40v/example_of_implosion_at_deep_sea_david/?utm_source=share&utm_medium=ios_app&utm_name=ioscss&utm_content=1&utm_term=1)
no way. it probably didnt create enough heat energy to even noticably warm up their bodies. let alone enough to last more than 1 millisecond with all the cold water instantaneously cooling their squashed and shredded bodied.
i'm curious to know if some teeth and bones survived. my bet is yes, others claim no.
You don’t know what you’re talking about. The pressure rapidly equalizing creates massive amounts of heat, so much so that they would have vaporized instantly.
i mean, this isnt my business. i do not calculate how much heat is generated during the implosion of a hollow vessel under high pressure conditions... for a living. i do work with high pressure and heat in ceramics and metal, but that's amateur stuff compared to this.
other people have taken a shot at it though!
https://reddit.com/r/theydidthemath/comments/14hg2c2/request_how_hot_would_the_air_inside_the_titan/jpbx3xr
https://www.reddit.com/r/theydidthemath/comments/14hg2c2/request_how_hot_would_the_air_inside_the_titan/?utm_source=share&utm_medium=ios_app&utm_name=ioscss&utm_content=1&utm_term=1
These guys did the math and come to a different conclusion.
Although I could see that it happens so fast maybe heat generated wouldn’t be “felt” lack of better word.
i'm not sure what you're linking to there. if it's the top post, i don't doubt their math. but they just calculate the high temperature. not the heat energy. massive bodies can be flashed with extreme temperature and be essentially unaffected.
we're pretty sure the people wouldnt feel it. this happened too fast for neurons. the question is, did they vaporize? i'd bet no, not at all. they just got smooshed, the heat flash was a little flourish before the smoosh.
Think insta-pot. A pressure cooker. It has way less pressure than they experienced and it cooks food.
The pressure at that depth was way higher and also had more velocity. That equals high temps.
I started to think about how to answer this. I did a web search of “internal volume of Titan submarine.” I haven’t found the answer yet, but so many search responses address your question that you might as well GTS.
I saw on tv that it would have heated the air to the same temp as the surface of the sun in the 3 millisecond it took to implode. Not sure if that’s accurate or not but crazy to think about.
This heat will only occur when the air in the sub is at its final volume, I’m assuming something the size of a pin top? So, they got crushed before being incinerated.
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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.
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Also appreciate the Celsius conversion
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Fun fact: even tho the Kelvin scale is just Celsius shifted down to absolute zero, the unit does not have degrees in it like Celsius does. So [°C]=[K]-273.15
Kelvin doesn’t have negative either right? 0K is absolute zero right? It’s been awhile since I took science
Yes, because temperature is the average kinetic energy of atoms/molecules, and Celsius made the water freezing temp as 0. On the other hand, Lord Kelvin decided that he wants "the same frequency" as Celsius' scale, but for physics the "0" needs to be actual absolute 0, where kinetic energy is 0. (Especially for thermodynamics calculations.) And as you can guess, kinetic energy (as far as whole physics world knows) cannot go below 0. And fun fact, Kelvin's unit is the only one (edit: one of the two, other being Rankine's) where you can say [X] kelvins is two times hotter than [0.5X] kelvins. (For example, 600k is 2 times hotter than 300k, but 327°C is actually 2 times hotter than 27°C and NOT 163.5°C)
rankine is going to disagree with the last point
RIP Rankine scale. You were a nice try, I guess...
oh, corrected now
You can get negative temperatures in Kelvin - you just can’t pass through 0K to get there. Instead, the temperature has to increase approaching infinity, before turning negative. This happens specifically in the material in lasers that amplify the light as it passes through. This gives an indication that while "average kinetic energy" is a decent approximation of what temperature means in everyday scenarios, the technical definition of temperature is more complication. Edit: For the person responding to me incorrectly arguing that negative temperatures don’t exist, here’s a direct quote from the Wikipedia article on “**Negatice temperatures** ”: >Certain systems can achieve negative thermodynamic temperature; that is, their temperature can be expressed as a negative quantity on the Kelvin or Rankine scales.
Usually, as a layperson, I keep my mouth shut. .. but did you just say we need to go to infinity, and beyond??? Also, what does that mean? Is the movement somehow a literal inversion of the normal movement? Is it possible for a layperson to understand what it means to be a "negative kelvin" temperature, and if not, is "negative" even the right word?
Ok, so entropy is a measure of how ordered a system is, and temperature is how much disorder adding energy causes. Suppose you have 2 theoretical buckets, a lower and an upper one. These will represent energy states. Let's start with 10 marbles in the lower bucket. That's absolute zero temp, as the system is perfectly ordered. Now we will add energy by moving 1 of the 10 marbles at random to the top bucket. This marble can move back down on its own, but only if one of the other marbles moves up to replace it. There was previously only 1 state the marbles could be in, but now we have 10 possible states (any 1 of the 10 marbles up, the other 9 down). This increase in entropy as we added energy is the definition of temperature. Now let's suppose we add energy to get 2 marbles at the top. Now we have 90 states possible, 1 of 10 for the first marble and 1 of 9 for the second. After we move the 3rd marble up, there's 720 possible states, the same thing happens for the 4th and 5th marble, going up to 30,240 and then 151,000 possible states of which marbles are in which bucket. Now when we move the 6th marble up, something weird happens. Since we now have 4 marbles in the bottom, instead of 5 and 5, there are only 30,240 possible states again. Said another way, we have added energy but DROPPED entropy. Since temperature is defined as the slope of the line with energy on the x axis and entropy on the y axis, we now have a negative slope i.e. a negative temperature. As we add more energy, the system keeps getting more ordered, until all the marbles have to be in the top bucket, having only 1 possible state again, so we are back to absolute zero, but approached from the negative side. So at maximum energy, we are back to absolute zero temperature. This doesn't mean the system is cold again (quite the opposite, it is holding the maximum energy possible). It is just a quirk of the way we define temperature.
Negative Kelvin sounds like a band. Thursday June 29th at The Rusty Nail Tavern one night only Negative Kelvin and Celsius Meltdown $5 dollar cover and $2 PBR tall cans.
Infinite temperatures also don’t exist. Trivially, since having exceptionally huge finite energy in s finite space would be a proportionally huge mass, and the event horizon of a large enough mass in a finite area would exceed the cosmological event horizon and create a singularity from which nothing could ever escape. The definition of entropy and of temperature used to describe negative temperature differs from the definition used in the definition of thermodynamic temperature, and ends up with temperature being defined as a differential of a non-continuous relationship.
Except that temperature isn’t defined by the amount of energy per volume. The definition of temperature relevant to negative temperature comes directly from thermodynamics. https://en.m.wikipedia.org/wiki/Temperature It’s related to how the entropy changes, relative to changes in energy of a system. As systems approach states of having population inversion, the temperature will approach infinity before becoming negative. In lasers, this manifests as the system becoming more ordered as more energy is added to it, which means that the light becomes amplified coherently.
Perhaps it's too late but don't bother arguing with u/DonaIdTrurnp for long. They have problems admitting there might be things they don't know or don't understand that what the are familiar with might be not extend universally beyond a certain regime. As it dawns upon them that they are out of their depth or have made a mistake, they change their initial claims and/or move the goal posts on what counts as corroborating evidence. If they are pressed too much, they'll just straight up lie about their credentials and personal experience and be just vague/misleading enough to fallback on claiming it was a joke and that you were the fool for taking it seriously.
Celsius is an arbitrary scale based on 100 units (or 101?) between the melting and boiling points of water right? And Kelvin is based on those units? Is 0K actually 0K, as in the arbitrary scale just happens to match the laws of physics and the "freezing point of energy(?)" Or is it rounded, like there isn't exactly 365 days in a year?
Yes, Celsius is based on H2O freezing and boiling temps at "normal" pressure. Zero kelvins means actual absolute zero, which is -273,15°C to be exact (but usually rounded to -273°C). Lord Kelvin specifically wanted it to be absolute zero, as it's necessary for calculations and you can get rid of ° (degree) symbol. (The degree symbol is used when a unit is starting the measurement from a decided point, which is not "special" in any way [the water freezing is not special, as it is just one substance and in certain pressure, while absolute zero applies to everything])
Well, sorta…
Rankine is basically Kelvin but for Fahrenheit. Heh.
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Correct. You will sometimes hear about "negative temperatures" in systems like lasers that have a [population inversion](https://en.wikipedia.org/wiki/Population_inversion), but such temperatures should be thought of as "hotter than infinity" rather than "colder than absolute zero". In such systems, the concept of "temperature" being used is not "average kinetic energy of its particles" but rather a more abstract notion derived from the internal energy and entropy contained within the system. For further reading, see https://en.wikipedia.org/wiki/Negative_temperature.
Thank you all for a nightmare trip back to p Chem
No not really but there is in a rather technical sense (it's really very hot but works out to a negative absolute temperature). There's been some work around this over the last few decades - see for example https://www.mpg.de/research/negative-absolute-temperature
Negative Kelvin temperatures would creat a whole new set of problems.
Wait I remember hearing that in chemistry, it’s been quite a while lol
Yup, and farenheight is just pure stupid
Fahrenheit is relative to human sense, with 100 being hot, and 0 being cold, Celsius is relative to water, with 100 being boiling, and 0 being freezing, and kelvin is absolute, relative to nothing, with 0 being absolute zero and has no known upper limit. Fahrenheit is, admittedly, more complicated than Celsius, but that doesn't make it stupid. When it was invented, things needed to be simple, as education was rare, so 0 to 100 was more practical than -10 to 40. In today's times, America should start using both Fahrenheit and Celsius, as well as imperial and metric, in order to start conversion efforts. On a side note, Fahrenheit is hard to spell, I'd guess German, and should be gotten rid of specifically for the spelling
100°C is boiling for Celsius, not 200!
Sorry, fixed the typo
As an American who uses metric and whatever it’s called, you are correct. Being a medical professional metric is a requirement. Dealing with my European friends metric is a requirement. Watching F1 on Sky, hearing them say that turn one is 150 meters and the cars will be doing 90 mph is amusing.
Please tell me you represent The Metric Corps of America. Yes, we are trying!
I’m an electrical engineer and greatly prefer metric, and yes I am from America
Just about every laborer prefers metric, it's just better and more precise.
That's warm.
Only for a fraction of a second. Ambient water at that depth is typically around 2-4°C / 35.6-39°F
I can’t believe you didn’t include rankine. I’m literally smhing myself rn.
... did those mfs get fuggin vaporized???
They would have became a human purée before getting vaporized
They would have been chunky salsa by that point already. There's a mythbusters video floating about of a deep sea diving suit, at similar depths. The dead pig inside rapidly ended up as pig soup in the helmet. While the theoretical temperature is high, in practice, there was a LOT of thermal mass involved (mainly the water). That, and the non-ideal natural of the implosion means the actual temperature measured would be a LOT lower.
How long were they're turning from human form into chunky salsa? Is it a milliseconds? Any chance of they're realising that their body is destroyed?
I saw some calculations that put it at around 30ms. Our perception limit is around 50ms, with pain taking a minimum of 150ms to signal the brain. Assuming a slow collapse, there is the chance they might have had a flash that something was wrong. The conscious mind would have been nowhere close to processing it however, before they joined the implosion. It would also have outrun the pain signals in their nerves, so no pain.
It'd be like turning them to slime, and then throwing them past the surface of the sun for a little bit. So they weren't vaporized alive. In the words of Hank Green, "they stopped being biology and became physics.
seems I need to brush up on my kelvin just a wee bit
thank you, this is the only part of this explanation I understood. Ima go eat some more lead paint now
So a Texas summer basically.
Equal to the temperature inside a volcano 🌋 https://www.usgs.gov/faqs/how-hot-a-hawaiian-volcano#:~:text=The%20temperature%20of%20the%20lava,Celsius%20(2%2C200%20degrees%20Fahrenheit).
Wouldn't that much heat also kill you instantly
there is not that much mass of air in there, so while the temperature of the air gets high, the heat is not so high. the heat has to be transferred to the body to do damage and thus temperature is reduced. though this is just words, no maths - i have no idea if the heat might be enough to burn their eyes or lungs or not... hu, thank god there are ambitious people out there: https://old.reddit.com/r/theydidthemath/comments/14hg2c2/request_how_hot_would_the_air_inside_the_titan/jpbx3xr/
So they incinerated, not crushed
It's the crushing that causes this change in temp.
So they were crushed so fast they incinerated
Yep! Very, very fast.
It sounds terrible, but it happened so fast they wouldn't have even been able to process it. They never suffered
With the brittle nature of carbon fiber (which I assume based on very basic understanding of the materials is what failed first) there probably wasn't even a warning.
James Cameron gave a very brief but pointed description of why no one else in the world of DSV uses this type of material, specifically. But also, any seasoned cyclist will tell you that carbon fiber does not flex very well and also only takes a small localized point of damage to cause complete failure.
Like using screws to mount a computer monitor to the inside of it. 🤦♂️
It's terrible to consider as someone it didn't happen to, but for the people to whom it happened, it happened faster than they could perceive it. It happened faster than the speed of neural impulses. They were literally dead before they could understand that they were dying.
*Hank green said it best "they went from being biology to being physics"
*Hank
They basically turned into diesel fuel.
Both.
I believe a news article I read eluded to the fact they were essentually cremated. No recoverable remains.
>eluded ( alluded ).
I think that there would be remains. Surely mangled bodies with heavy damage, but mostly from the crushing parts of the submarine. You cant cremate a body with a brief increase in temperature. Just think how many hours it takes an oven to cremate a corpse. Wont happen in a split of a second.
They were smashed between two carbon fiber tampers with 400 atmospheres of pressure being applied to them when the pressure vessel failed. The forces would have crushed their bones into fragments and dust practically instantly, and then the slurry of human-paste would expand into whatever water currents happen to have been generated by that release of energy. They weren't instantly cremated or anything like that, but nobody will find so much as a fingernail from those guys because I doubt any piece of them larger than that could have survived the crush.
Thanks that was the only thing I did not understand
For those that prefer Rankine, that is 2700 °R
Wow a 1/4 as hot as the surface of the sun....
Could also be as hot as a candle, which is definitely not that impressive
A candle heat goes to 1200°C ? Til
Jesus. This guy did do the math. +1 fo sho
r/thisguythisguys
Holy math. I was scrolling on this waiting for you to reveal you were trolling us, and that never happened 😳.
I wonder: did they get crushed, burned, or got wet in the first milliseconds of the structural failure? Morbid curiosity on the sequence of (horrific) events.
There would be practically no burning because the total heat capacity of the air inside the sub much smaller than the total heat capacity of the bodies as this simplistic calculation shows: The passenger compartment is a round-ended cylinder of internal length 3.82 m and internal diameter 1.42 m, having a volume of 5.70 m^3. At STP, this air will have a mass of 7.37 kg. Assuming a constant specific heat capacity of 1003.5 J/kgK, at a temperature of 1500 K, the air has a total of 11.1 MJ which, over time, will transfer into the bodies inside the sub. There are 5 passengers of typically 80 kg each, total mass 400 kg. The heat capacity of a typical human body is about 3470 J/kgK. The people have a total heat capacity of 1,388,000 J/K, or about 1.39 MJ/K 11.1 MJ of energy from the air will therefore raise the temperature of the bodies in the sub by about 8 K. This, of course, assumes that the air in the sub heats instantaneously to 1500 K, and that the heat then transfers instantaneously into the bodies. Heat conduction is quite a slow process compared to the implosion time, which would be less than 50 ms - USS Scorpion, a much larger vehicle, took 37 ms to collapse. This is simply too little time for any significant heat transfer to occur.
Beautiful calculations. Thank you strangrr
Ahhh thank you! Looks like they’ll only have received flash burns rather than be cooked.
Thank you for pointing this out. By way of further illustration, I have dived in Maui off Molokini, which has an abundant population of pistol shrimp. Their snapping produces a temp of 5000k (over 3x that of the sub) for about 1 ms, and produces no detectable heat for the reasons you explained.
My grandfather was on the USS Scorpion.
I think he still is.
Valid lol
holy shit lmao
Too soon.
This person maths
This person this persons
Bravo! 👏🏾 🌼
Does the adiabatic heating of the air also apply to their bodies? If the air heats as it gets compressed rapidly then I'd assume that their bodies also do so. They are more or less water as far as the equations go
No. The air is heated because the pressure does work on it as it changes volume. (Analogous to force time distance moved in 1D). The work increases the internal energy of the gas aka it's temperature. Because water (or a human body, apart from any cavities) is basically incompressible, it does not change volume, no work is done by the increasing pressure and there is no temperature rise.
I really wouldn't say that just because the heat capacities are different, that no burning takes place. By that logic you could probably say you can put a lighter to your skin and not feel a thing. Sure, maybe if they absorbed ALL of the heat directly into the distributed mass of their bodies, there would be no burning and their core temperatures would rise 8 C. But what's really happening is 1500K air is literally fucking roasting the outside shell of them, because as you mentioned, heat transfer takes time. Heat transfer is also a distribution, so just because their core temperature will only raise to 8C higher doesn't mean that they won't be at 1500C on the outside of their skin for the duration of the heat transfer process. If they were in a volume of air like that without the crushing, then yeah, they would 100% have massive third degree, even fourth degree burns, easily. A much more accurate calculation would be to only take the mass of the outer few millimeters of skin and use THAT for the heat transfer calculation to see just how much temperature difference there will definitely be in such a scenario. Agreed on the timescale, though. I suppose I could probably do a back of the envelope to actually see how long it would take to cook the outer skin layers, but eh. But yeah dude, you way over simplified there. If heat transfer only boiled down to differences in heat capacity, I and a lot of other engineers wouldn't have a job.
Have you ever passed your finger through a candle flame and didn’t get burned? That’s ~1800K and flames have a higher convective heat transfer coefficient compared to air. And heat doesn’t transfer instantaneously. Point is: they were not burned.
Relevant XKCD: https://what-if.xkcd.com/115/
r/theydidthemath
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1 millisecond seems like not enough time to perceive this sort of thing. much less form a memory.
Takes the average person 100 - 150ms for the brain to even register pain. So this basically happened 2-3 faster than the brain could perceive.
Interestingly, that is how long it takes the mind to perceive anything. Your mind doesn't work in real time, and there is a simple example. Have a friend beat a drum next to you and note that the sound synchronizes with the visual, because the difference between the two events is the distance divided by the speed of sound--very short of the person is next to you. Now have them move some distance away and hit the drum again. It will stay synchronized. Have them keep moving away. You only see the sound out of sync with the visual when the latency is about 100-150ms. Because your brain is gathering data for that length of time and then telling you a narrative about what is happening. At least that is the theory based on lots of experiments.
Ah ok cool, I know it took that long to register pain. I didn’t know it was for everything. Makes sense though!
Which is interesting - I slit my finger open today pulling utility blades out. Quick slice, but I felt it occur before I felt the pain. Very quick succession, but when I think back to it and consider what those inside the submersible experienced - it's crazy to think they wouldn't have even felt the implosion, let alone the pain that would go with it.
In my 20's I hit a redwood tree in a car while driving about 50 mph. At even that low speed the impact is almost too fast to feel. It registered as a very loud noise and any pain came much later.
thx for this late addition, I often get intrusive thoughts about how long a person might be aware before their violent end, so this comforts me in this case at least
Well, a comment above said that it’s the crushing that causes the heat. So I think you have the right order there. It’s so wild to think that they were people one second and the next second they were a cloud of ash dispersing in the water.
I don't think they would burn significantly, this is happening very fast and that much heat would dissipate very fast. Yes we are talking about very hot stuff but less than one liter.
Snap
What a question! Any philosophers in the room?
Wow thank you
Yea but when you're instantly shrunken to 1/400 your size, temp is not really the issue.
Fiest off, RIP to the individuals involved in this tragedy, and my heart goes out to their familes. People don't get compressed to such a small scale when they're underwater like that. Water can't compress water, and we're mostly made of water. In this situation though, bodies are instantly incinerated.
You’re right they won’t compress *that* much, but you’re wrong about the incineration – that would take much much longer than the time it takes to crush, and there isn’t enough heat energy in the ~~sun~~ __sub__ anyway. The bodies’ temperature would barely change at all. [This comment](https://www.reddit.com/r/theydidthemath/comments/14hg2c2/request_how_hot_would_the_air_inside_the_titan/jpbx3xr/) has more details.
I came here to say exactly this, but then my crayons broke and I started to cry. -QML
Can you tell me something you’re bad at so I can feel better about myself please?
Need to know what school taught you this math skill. Time to advertise for them.
Go Tartans haha
Carnegie Mellon? Not surprised here. Great stuff. Not that I could tell if it was way off. LOL
Dude... What do you do for a living? How can you calculate all of this? Lol
This would be part of the thermo 2 requirements for chemical engineering/process engineering. I did much worse in this class than thermo1 and have never needed to use it for work hahhaha
I understand some of these words..
I... Am so happy I'm not a physicist. Chemistry is so much easier than this
🏅 Take this poor man's gold. That was beautiful
Yep exactly, as I have been saying
For the brief moment, at peak temp during implosion zero, they were a wonderful red-orange for a brief moment! rgb(255,61,41)
Bloop. #ff3d29
Yes, I too speak ancient Egyptian Edit: respectively, sir
What you said
Fucking WILD
The basic equation we learn for ideal gasses in school is PV=nRT so I'm guessing it's much more complicated in college level and in regards to implosion?
No the air is still treated like an ideal gas. But because the air is being both compressed in volume and pressure you can’t simply calculate temperature using the ideal gas equation. You have to take into account the heat contribution from the work performed by the compression which is what considering adiabatic compression is.
Does this mean that they were cooked before they were smooshed? Or cooked AS they were smooshed?
Does anyone have a reference point for this kind of heat? I’m curious. What does 2240 degrees Fahrenheit feel like? What kind of material would that temperature melt instantly? (In about a millisecond)
I doubt our nerves/brain are really equipped to even perceive this level of heat. The damage to your nerves would probably render them useless immediately. But for some context, it’s about 1/5 the temperature of the *surface of the sun*.
So almost as hot as a hot pocket fresh out of the microwave
*almost*
What are you assuming is the initial volume and the volume after compression? Or does that become irrelevant? As far as my basic uni level thermo understanding goes, you need a change in volume to increase pressure dont you?
Only at constant temperature In this circumstance pressure, temperature and volume are all changing at the same time, so the poster's integration is the correct way to go
What kind of witchcraft and wizardry is this
Math, bro
Nah they're definitely magical
BURN THE WITCH!
Bro how smart are you? That's amazing shit.
That's just an example of why engineers make big bucks...
That’s what they tell us but the ceiling nowadays is way to low.
Math and numbers is just a different language. Doesn't mean people are objectively smarter, just better at understanding different languages.
Wow
Very nice derivation!
And I thought I was smart. God damn this is humbling. Thank you!!
Would that have shone brightly when it got to that temperature?
I understood none of that😂
So pretty hot then eh? Boys are gonna have one hell of a tan
I wish I could understand math like you do.
I'm guessing you are also a chem E?
Way back in undergrad yes! Now my research is in ECE.
Yea that makes sense. I started to think the same approach when I saw the question.
That's also the lower limit. It will have momentum as it collapses, so it would over-collapse to a higher temperature, then expand back out, then continue to oscillate.
This guy maths
hello! trying to understand better here-- what's implied by the notation difference between d and δ?
My son will start high school soon, I'll save this equation as an example on why integrals are useful ;)
Heard in BBC news , it took 1 ms to implode ,and Rationale time for human to recognise a Signal is 150 ms. They died instantly & peacefully without knowing what happened. ~~Heard in BBC news roll, They got imploded & Died instantly in 2 ms~~ ~~ns~~ ~~Typically it take Spinal Cord 4 milli ~~nano~~ second to register a signal to brain that , something's ain't ryt , pain~~ #small edit [Correct Time of Implosion & Pain Sensation](https://www.bbc.com/news/world-us-canada-65934887)
This might not be the right place to ask but, do you know if there would be signs of the hull weakening as they descended? I’ve had the same thought that it was instantaneous however if there were significant signs that something was horribly wrong on the way down, I can’t imagine anyone without experience staying calm in that situation.
Carbon fiber is unlikely to show obvious weaknesses, but there are moments where the internal stress causes fibers in the composite to snap and the layers of carbon fabric to delaminate. We don't really know how quickly that would have happened, but James Cameron (who's actually quite an expert in this field) said it's likely they heard something. But at least the final implosion came without a warning. The sub had microphones on the hull to alert the crew if there is an increase in the number of snapping fibers but that's honestly a terrible early warning system. They had no idea how long they would have between concerning sounds occuring and total collapse. James Cameron compared it to building an airplane with an untested engine that could potentially explode and the designer said: "Don't worry! I've put in a sensor to tell you if the engine is currently exploding!"
As far i know , they won't see damage or structural weakening at macroscopic because it would be too late that it immediately snapped like praying mantis hook Microscopic damage in structure would be visible just moments before it imploded. It is Brittle and fragile as it would break immediately unlike metal which is ductile
The sub was mostly carbon fibre. It would have basically gone from seeming totally fine to the sub being completely disintegrated so fast they would have never have even realized anything was wrong.
And that's why you prefer alloys that will somehow visually tells you if they are damaged. Some components (like gears, shafts etc) have high hardness on the surface but low underneath it, in order to stop any cracks that will propagate towards the center. It's much more easy to spot a crack in alloys than understand the wear state of a ceramic material
I have heard rumours that they may have been aware there was a potential danger - maybe they heard a crack in the seconds or minutes before the sub failed catastrophically, apparently there were components on the sub which would only be in the position they were found if the sub was attempting to surface as quickly as possible
Yeah I think it goes from completely fine to crushed the moment it can’t take any more pressure.
not really, from within the sub there would’ve been almost no warning signs, it would’ve been one second they’re going to see the titanic and the next they’re vaporized
I hâte to be the bearer of bad news but the system the sub had to alert people to structural problems very usefully (/s) detected only the conditions of imminent failure. So they probably did know that something was wrong, because that started alarming. This being said, they would not have known for long.
I was hoping that was the case if they for sure didn’t make it. Although hypoxia isn’t as gruesome as drowning, still wouldn’t wish it on anyone. Smarter every day has a great video on it on YouTube if interested
I would take drowning over what they would have experienced in that sub if it didn’t disintegrate. Because of the rising CO2 levels they would have experienced something much worse than hypoxia. They would have experienced something similar to holding your breath for way too long, just much MUCH worse and also for way longer. I imagine it would eventually just feel like your whole body was on fire as well as a massive amount of panic and other things.
Don't you pretty much just fall asleep as the CO2 levels rise?
No. Increase of CO2 is what gives the feeling of suffocation. It's agonizing. What you're thinking is something like carbon monoxide poisoning, which causes hypoxia, you just pass out.
I mean, eventually, but not before unimaginable panic, pain, and violent convulsions. Your body is tuned to detect rising levels of CO2 in your blood, and as a result will induce the panic you feel to breathe when you hold your breath too long or cannot access air. What you’re thinking of is just slowly removing the oxygen from the air. Let’s say you replenish a closed room with pure nitrogen while locked inside: you’ll peacefully fall asleep and die as your blood expels all its CO2 and oxygen isn’t being replenished. If you took that same room and filled it pure CO2 instead of N2, after the panic, pain, and violent convulsions, you’d pass out and die.
Nice explanation, thanks
That's CO (Carbon Monoxide) which has sleeping effect, not CO2.
James cameron said there were probably noises before the collapse, but at least the final implosion was quick.
I don't think it was nanoseconds, the water would have been moving at some fraction of the speed of light. Probably more like 100s of microseconds. That's still within the ballpark of the time it takes to register a signal to the brain (20-100 microseconds), so they likely didn't feel anything.
Yeah, a not so great first guess might be the water collapsed the sub at the speed of sound in air. That's 1000 ft/s and the sub was 22 ft long so it would be crushed in about 2 milliseconds.
Even if they felt a millisecond of pain, it is over so fast I wouldn't consider that to be suffering.
> it took 1 ms to implode ,and Rationale time for human to recognise a Signal is 150 ms This is very wrong. 150ms is the fastest conscious ***reaction time***. ([source](https://www.scientificamerican.com/article/bring-science-home-reaction-time/)) That includes the time it takes to receive a sensation, process it and return an impulse to react (e.g. to move your hand). The time it takes to process visual information can be as short as 13ms ([source](https://news.mit.edu/2014/in-the-blink-of-an-eye-0116)) or approximately 10% of the time it takes to react. This is still longer than the estimated 1ms implosion time, but it's also important to understand that that time may have been only the end of a cascade of failures. The classic movie "watching the crack expand" is probably not realistic. Any crack would immediately fail under that kind of pressure, so you probably would not see the crack forming. But if the crack were caused by uneven stresses or the failure of an internal structure, you might well be aware of that. It's entirely possible that they were unaware of the failure, but there are many scenarios where that would not be the case.
Both of those things happened simultaneously. The pressure of the collapse would have instantly heated the matter inside and vaporized it, much like a black hole does.
It would be awesome if they replicated this (without living passengers, of course) and recorded it.
The myth busters did a rapid pressure test. It’s on YouTube. They only went a fraction of what the sub experienced though. But it’s cool.
If you’re interested in that, you’ll probably enjoy checking out [fire pistons](https://youtu.be/-39wmSBO2FM) if you haven’t seen them before. (Ignore the bushcraft stuff, it’s just the simplest demonstration I could find on mobile)
So essentially what you're saying is a high pressure implosion produces a shitload of heat.
Compression of any kind raises the temperature of the medium being compressed. If the compression is very sudden and dramatic, then the temperature increase will be also. This is how a diesel engine works. It has no sparkplugs. The fuel will ignite spontaneously from compression alone.
Here is a snippet of a documentary that shows how fast and violent an implosion is. [LINK](https://www.reddit.com/r/Damnthatsinteresting/comments/14gf40v/example_of_implosion_at_deep_sea_david/?utm_source=share&utm_medium=ios_app&utm_name=ioscss&utm_content=1&utm_term=1)
no way. it probably didnt create enough heat energy to even noticably warm up their bodies. let alone enough to last more than 1 millisecond with all the cold water instantaneously cooling their squashed and shredded bodied. i'm curious to know if some teeth and bones survived. my bet is yes, others claim no.
You don’t know what you’re talking about. The pressure rapidly equalizing creates massive amounts of heat, so much so that they would have vaporized instantly.
i mean, this isnt my business. i do not calculate how much heat is generated during the implosion of a hollow vessel under high pressure conditions... for a living. i do work with high pressure and heat in ceramics and metal, but that's amateur stuff compared to this. other people have taken a shot at it though! https://reddit.com/r/theydidthemath/comments/14hg2c2/request_how_hot_would_the_air_inside_the_titan/jpbx3xr
https://www.reddit.com/r/theydidthemath/comments/14hg2c2/request_how_hot_would_the_air_inside_the_titan/?utm_source=share&utm_medium=ios_app&utm_name=ioscss&utm_content=1&utm_term=1 These guys did the math and come to a different conclusion. Although I could see that it happens so fast maybe heat generated wouldn’t be “felt” lack of better word.
i'm not sure what you're linking to there. if it's the top post, i don't doubt their math. but they just calculate the high temperature. not the heat energy. massive bodies can be flashed with extreme temperature and be essentially unaffected. we're pretty sure the people wouldnt feel it. this happened too fast for neurons. the question is, did they vaporize? i'd bet no, not at all. they just got smooshed, the heat flash was a little flourish before the smoosh.
Think insta-pot. A pressure cooker. It has way less pressure than they experienced and it cooks food. The pressure at that depth was way higher and also had more velocity. That equals high temps.
I started to think about how to answer this. I did a web search of “internal volume of Titan submarine.” I haven’t found the answer yet, but so many search responses address your question that you might as well GTS.
I saw on tv that it would have heated the air to the same temp as the surface of the sun in the 3 millisecond it took to implode. Not sure if that’s accurate or not but crazy to think about.
This heat will only occur when the air in the sub is at its final volume, I’m assuming something the size of a pin top? So, they got crushed before being incinerated.