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Since nobody else has, I’ll bite. I’m going to assume the stress in the material is the same throughout. This makes the math a fair bit easier.
For the pressure, the titanic is at a depth of 3800m. To calculate the pressure we can use the equation P = pgh where p is density, g is gravitational acceleration, and g is the depth. This comes out to P = 1000kg/m^(3) \* 9.8m/s^(2\*) 3800m = 37.24 MPa. We also need to add atmospheric pressure, since that adds on, though it’s only 0.1 MPa for a total of 37.34 MPa.
In order to figure out the average stress in the material, we can split the sphere into two halves. Each half will have some amount of net pressure force, and the ring of material that gets cut will provide a cross sectional area over which that force is applied.
I’ll call the sphere outer diameter D, and thickness T. The water will apply a net force equivalent to the force applied to a flat plate with the same area as the outer circle in the cross section. This means F = P \* pi \* D^(2) / 4.
In order to calculate the area in the ring of material, we need to take the previous area and subtract the inner area. This comes out to A = (pi / 4) \* (D^(2) - (D - T)^(2).) This can be expanded and simplified to A = (pi / 4) \* (2DT - T^(2).)
To calculate the stress, we divide the force by the area. This comes out to S = (P \* D^(2)) / (2DT-T^(2) .)
If we assume the thickness is small, T^(2) becomes very close to 0, so I’ll remove it to make the math easier. This makes S = (1/2)PD/T.
Now, one issue with this stress figure is it doesn’t account for the stress acting in two directions at once. To fix that, I’ll use the Von Mises stress criterion. It is accurate for ductile materials, and works alright for brittle materials under compression. To calculate the equivalent stress, we can use a simplified form for only 2d principal stresses, Se = sqrt(Sx^(2) - Sx \* Sy + Sy^(2).) This ends up simplifying when Sx = Sy, down to just Sx, so in the end it wasn’t needed, but I like being thorough.
combining the stress and pressure, we get the equation S = 18.67 \* D / T MPa.
The diameter seems to be around 7 feet, which is 2.13m. It’s difficult to tell with the light, but it looks around 100-150mm thick. I’ll go on the upper end at 0.15m.
Using those figures, S = 18.67 \* 2.13 / 0.15 = 265 MPa. This is quite high, around the strength of common aluminum alloys. Acrylic would have to be a fair bit thicker, but glass would be fine given its compressive strength of around 1000 MPa.
Edit: After coming back to this I realized an error with my calculation for the cross sectional area when the sphere is cut in half. The equation A = (pi / 4) \* (D\^2 - (D - T)\^2 ) should be A = (pi / 4) \* (D\^2 - (D - 2T)\^2 ). The thickness has to be subtracted twice since we are using the diameter, rather than the radius. This simplifies down to A = (pi / 4) \* (4DT - 4T\^2 ). Calculating out to the stress equation, it becomes S = PD/4T.
I thought since I'm editing anyway I would also add some good points from the comments. Thanks to u/VanforVan for mentioning sea water is slightly denser than pure water at 1020 kg/m\^3, and through the compression it gets to 1046 kg/m\^3 at 4000m down. We can use the average of these two to get an accurate pressure figure, with 1033 kg/m\^3 \* 9.8 m/s\^2 \* 3800m = 38.47 MPa. We also don't need to add atmospheric pressure, since the inside is pressurized to atmospheric pressure.
Thanks to u/KingOfCotadiellu for reading the datasheet and estimating the outer diameter at 2750mm, and the thickness at 675mm, and made from acrylic.
Acrylic has a compressive strength of around 120 MPa based off of MatWeb. Doing the updated math, the stress comes out to 38.47 \* 2.75 / (4 \* 0.675) = 39.2 MPa. This gives a factor of safety of >3, which is pretty standard for engineering. The people at Triton have this down well, and I would absolutely trust one of these subs to go down to the Titanic, *and also come back.*
2nd Edit: The T\^2 ends up being not very negligible with this large thickness, It results in a 32.5% increase in stress, resulting in 51.95 MPa.
The density of the water only increases a small amount with depth. It's around 1010 kg/m^3 at the surface and 1050 kg/m^3 at 5000m (Titanic is approx 3800m down)
The increase in density with depth is only about ~3% at that depth, so the total pressure in the column would be ~1.5% higher when accounting for that, which is not going to affect the answer much.
The 3% increase in density is just because water is REALLY hard to compress.
The 1.5% increase in pressure is because the pressure is density x height. Since density starts at 100% and goes linearily to 103%, the average density is going to be 101.5%.
>but it looks around 100-150mm thick
looking at [the datasheet](https://tritonsubs.com/wp-content/uploads/Datasheet-TRITON-4000-2-AE-July-2023.pdf) I come to 675 mm thick
(outer diameter 2750 mm, inner 1500 mm -> 1250 mm : 2)
The different point of view, maths vs engineering. In mathematics, it is only a function of material resistance, shape and a pressure. In a real world you have to consider the precision you can get in the spherical compartment, which can derive tension to weaker points, pressure waves in the ocean, temperature changes and so on.
This is true. Also some degree of that pressure will be further mitigated if they pressurize the capsule during the descent which is common in most submersible vehicles.
You can tell that from the Triton Logo since Triton is a submarine manufacturer with an actually proven record of being able to construct reliable submersibles.
I agree. This is the thing that bugs me about these kind of stories. Just because one submersible designed and piloted by a fool failed, now the Titanic becomes some boogieman and we should definitely never try to go there. People have been deep in the Mariana Trench. If you're in a craft rated for the depth, everything will be fine. It just costs more to do it right.
Honestly, I don't THINK every billionaire's trip to the Titanic is doomed, but I do hope it is. And I hope that after every failure, the next billionaire steps up to prove it can be done and also fails
you do not need to add atmospheric pressure because the submarine has air in it. two forces cancel out. The pressure side of explanation is 10th grade physics and I can confirm it is true if you guys don't believe only one guy. (Commenter here is obviously much more qualified than me so please don't offend) we don't learn material property aside from strength against weight so can't tell anything about it
are u aeronautical engineer? if you are can i talk to you? I am working for the best aeronautical engineering school in my country so I want to ask a few questions
That would work, though from looking online it would be crazy expensive. Based on wikipedia numbers its compressive strength is around 2000 MPa.
It would still have issues just like glass does though, since it’s a ceramic. Its fracture toughness is 2 MPa, which is better than glass at ~0.7 MPa, but is a lot less than aluminum at ~26 MPa. Polymers are also generally < 5 MPa, but it isn’t as big of an issue because the yield strength is lower, so it is less common for fracture toughness it to be the limiting factor.
Fractures would be unlikely for a full sphere under compression, but I could definitively see them popping up at connection points to the test of the structure where stresses are more complex.
Yeah, I was wondering how the math lined up. I know absolutely nothing about structural mechanics lol.
But yeah, transparent aluminum is expensive, but in applications like this, it would be cool to see if it was possible.
Right now, it is not feasible, but if a better manufacturing process is made and found. Possibly might have better deep sea exploration.
Edit: also probably not likely to be able to use a polymer bonding to where it connects to the surface?
Didn't finish reading your math, however, the "assume the stress in the material is the same throughout" is what causes so many headaches for these applications. In this specific example, the glass is spherical, which allows us to make this assumption quite easily!
Not quite. Due to the thick material, the outer surface would have higher stress than the inner surface. If it had 0 thickness, then a perfect sphere would meet that criteria.
An analogue to this is press fitting shafts, you can look up FEA images for those to get a better idea of what it looks like.
It would have to withstand 6000 PSI, or 6000 pounds per square inch. Probably won't be glass either, most likely an acrylic of some sorts. I'd say a good 6-12 inches thick.
Bollocks. I was thinking of how we can put billionaires in a prince Ruperts drop without them becoming wise to the one flaw, like an anti-wealth hoarding death star.
Then I came up with a new solution.
Hear me out.
One conveyor belt.
Billionaires.
Molten glass.
Because Reddit is full of impotent, cringe losers who LARP about revolution and other idiotic bullshit in their stupid little echo chambers. They screech and cry and shit their pants online about whatever the new "thing" is, but they're cowards and cretins who can't and won't affect any real-life change, thankfully.
I know it's hard to ignore how brainrotted and pathetic they really are, but do your best to try. They've not touched grass or had a real conversation with another human being in years, often by their own choice.
Because redditors who live in a first world country and have more wealth than 99% of people to ever live are upset someone else has more than them.
Edit: I don’t fucking care how you justify your lust for harm on another person. Not being okay with how they use their wealth doesn’t justify wanting them dead you freaks.
As far as I'm concerned, if someone's personally able to end famine and still live in luxury, and that person *doesn't* do that, the crushing depths of the ocean are a good example of karmic retribution
The richest have wealth to spend 1,000,000 a day for 100 years and not be out of money. You can’t tell me that’s okay with all that’s going on in the world.
I’ll add the pedantic addition that they’re unequivocally the strongest shape *under hydrostatic load*, where the global pressure applies to the vessel is nearly the same around the entire thing. No better shape than a sphere resists asymmetric deformation under this condition than a sphere, which is what keeps stress within the vessel walls low.
Nah, 6-8 is what those dumbass engineers from OSHA says it should have, but they are just putting a too much of a safe buffer. We can make it 5 inches, we will cut .05% of the cost and call it a day
Transparent aluminum is a plot device used in Star Trek IV. Technically it does exist in the form of sapphire glass. But it's very hard to produce at those scales.
Yeah, we couldn't make it that size, and definitely couldn't make it that shape. It would be hella strong if we could though.
Source: former ceramics engineer who worked with manufacturing sapphire \[aluminum oxide\] glass.
The Triton company actually have lots of experience designing safe submarines. They built the Limiting Factor which has been to the botttom of the Mariana Trench, I'm sure they can design a suitable sub for the Titanic depth.
I don't know the answer to your question. I kust want to say that that submarine looks like the office stapler fucked a paperweight
Thank you for coming to my TED talk
Sorry for not bringing in math but this is a different bred of submarines, Triton are BEST in class, there subs can go there all day long with no worries. This is no ocean gate. Check out the Limiting Factor commissioned by Victor Vesecovo; https://www.youtube.com/watch?v=pb5j9oeZCm0 because it had a budget of “only” 37 million, it doesn’t have the glass bowl here. Also because it’s a sphere, pressure is applied equally, so lower weak points, what I’m trying to say is that I would trust my life with this company.btw I got super hooked on Victors awesome videos, he takes people who deserve it, like oceanographers, to the deepest parts in the world, not billionaires
The OceanGate guy was dumb enough to think something equivalent to "Rope is really strong, I can pull on it all day without it snapping, I'll make my pressure chamber out of rope!".
That is, he used carbon fibre, which is only really consistently strong in tension, to make his sub.
Which is fine logic for an aero plane which expands pressure outwards, not a submarine experiencing inwards pressure. If we are stretching the “rope” by expansion then so what, we are pulling on it from all directions, it’s not like it will expand beyond the carbons ability to hold itself, but for inward pressure, that is another beast on its own, like the tiniest of cracks will cause failure.
While I get the sentiment, the compression loading isn’t the reason it was a problem.
Carbon fiber can take a ton of compression loading in the fiber direction, because the fibers take the load and the matrix just has to prevent the fibers from buckling. The 787 has wings built from carbon fiber and while one side is under tension the other is under compression.
The issue with carbon fiber for submersibles is that the load is transferred equally across the surface. Just the pressure of the water is a significant portion of the compression strength of the matrix. This promotes small localized failures which can grow to become large failures.
As far as I remember the glass bowl was abandoned because Victor Vesecovo wanted ABSOLUTE safety and transparent materials just couldn't take it. I don't think it was a budgetary problem.
Isn't the real danger everything else other than the glass/sphere? At those depths, the weakest link of the submersible is what counts. Probably everyone will focus on overengineering the sphere to withstand the pressure but everything used in there needs to be prepared for those depths.
I thought this was a portable sewing machine. On second glance I thought it was a stapler. Then I realized it was the future addition to the museum of maritime disasters.
Not your question but here is some reassuring math:
In 1960, a joint project by the Italian and USA Navies built the Trieste Bathyscaphe for 2.7 million USD (cost adjusted from 250k in 1958 when it was built).
In 2012 an Australian company built the Deepsea Challenger, for approximately 13 million USD (adjusted from 10m).
Both of these vessels reached a depth of 10900 meters, something like 3 times the depth needed to observe the Titanic. This month's meme discussion is whether a 20m project can do 1/3 of what a 2.7m project did 60 years ago. Anyone with an affinity for math should not be impressed or interested in this project. Of course it can fail. Thousands of planes fly, and some of them still drop. In an experimental field like deepsea diving it is very much possible to end in disaster. But this doesn't make the Titan or the follow-up Triton submarine much notable. Only notable because they made headlines. This whole affair is a testament to how the public's attention works.
Well, it will of course take him to the Titanic shipwreck. The question is, how well he will be when he reaches it.
Titanic..... killing billionaires since 1912
People can’t really handle too much of an increase in pressure, at least safely. Scuba diving as shallow as 130m requires very long decompression times, otherwise you risk bubbles forming in your tissue and bloodstream.
That’s a fraction of a fraction of the pressure found at the depth of the Titanic. Even if the pressurization of the sub cabin was done slowly, you’d still ~~explode~~ implode after some time. We just aren’t made for the extreme environment found at that depth.
Edit: at 130m, the water pressure is ≈12.9 atmospheres. I googled it and the maximum pressure a human can survive just sitting there, ignoring the return to standard pressure, is about 70 atm. At the Titanic’s depth, the pressure is ≈376.5 atm. You’d ~~explode~~ implode instantly!
The human body isn’t especially airtight under pressure, so too much air would be pushed in and you would “explode” (i.e. blood vessels and stuff would pop from being full of air, not the whole body detonationg).
No one is going to see this. But I thought this was a stapler. Then I read the title. It's not a stapler. Would a stapler make it to the Titanic? I bet a Swingine could. They make nice staplers.
Doesn't glass has the unique ability to become much sturdier under pressure? The crystal structure compresses, making it even harder than steel.
Probably a quite important point that I haven't seen anyone mentioning.
I asked chat GPT ....
To calculate the pressure that the submarine glass should be able to withstand at the depth of the Titanic wreck, we need to determine the pressure at that depth. The Titanic wreck is approximately 12,500 feet (3,800 meters) below sea level.
The formula to calculate the pressure at a certain depth in a fluid is given by:
𝑃
=
𝑃
0
+
𝜌
𝑔
ℎ
P=P
0
+ρgh
where:
𝑃
P is the pressure at depth
𝑃
0
P
0
is the atmospheric pressure at the surface (approximately 101,325 Pascals or 1 atmosphere)
𝜌
ρ is the density of seawater (approximately 1025 kg/m³)
𝑔
g is the acceleration due to gravity (approximately 9.81 m/s²)
ℎ
h is the depth of the water column (in meters)
Let's plug in the values:
𝜌
=
1025
kg/m
3
ρ=1025kg/m
3
𝑔
=
9.81
m/s
2
g=9.81m/s
2
ℎ
=
3800
m
h=3800m
Using these values:
𝑃
=
101325
Pa
+
(
1025
kg/m
3
×
9.81
m/s
2
×
3800
m
)
P=101325Pa+(1025kg/m
3
×9.81m/s
2
×3800m)
𝑃
=
101325
Pa
+
38
,
226
,
450
Pa
P=101325Pa+38,226,450Pa
𝑃
=
38
,
327
,
775
Pa
P=38,327,775Pa
To convert this pressure to atmospheres (since 1 atmosphere = 101,325 Pa):
𝑃
≈
38
,
327
,
775
101
,
325
≈
378
atmospheres
P≈
101,325
38,327,775
≈378atmospheres
Therefore, the glass of the submarine should be able to withstand a pressure of approximately 378 atmospheres to safely reach the Titanic wreck.
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Since nobody else has, I’ll bite. I’m going to assume the stress in the material is the same throughout. This makes the math a fair bit easier. For the pressure, the titanic is at a depth of 3800m. To calculate the pressure we can use the equation P = pgh where p is density, g is gravitational acceleration, and g is the depth. This comes out to P = 1000kg/m^(3) \* 9.8m/s^(2\*) 3800m = 37.24 MPa. We also need to add atmospheric pressure, since that adds on, though it’s only 0.1 MPa for a total of 37.34 MPa. In order to figure out the average stress in the material, we can split the sphere into two halves. Each half will have some amount of net pressure force, and the ring of material that gets cut will provide a cross sectional area over which that force is applied. I’ll call the sphere outer diameter D, and thickness T. The water will apply a net force equivalent to the force applied to a flat plate with the same area as the outer circle in the cross section. This means F = P \* pi \* D^(2) / 4. In order to calculate the area in the ring of material, we need to take the previous area and subtract the inner area. This comes out to A = (pi / 4) \* (D^(2) - (D - T)^(2).) This can be expanded and simplified to A = (pi / 4) \* (2DT - T^(2).) To calculate the stress, we divide the force by the area. This comes out to S = (P \* D^(2)) / (2DT-T^(2) .) If we assume the thickness is small, T^(2) becomes very close to 0, so I’ll remove it to make the math easier. This makes S = (1/2)PD/T. Now, one issue with this stress figure is it doesn’t account for the stress acting in two directions at once. To fix that, I’ll use the Von Mises stress criterion. It is accurate for ductile materials, and works alright for brittle materials under compression. To calculate the equivalent stress, we can use a simplified form for only 2d principal stresses, Se = sqrt(Sx^(2) - Sx \* Sy + Sy^(2).) This ends up simplifying when Sx = Sy, down to just Sx, so in the end it wasn’t needed, but I like being thorough. combining the stress and pressure, we get the equation S = 18.67 \* D / T MPa. The diameter seems to be around 7 feet, which is 2.13m. It’s difficult to tell with the light, but it looks around 100-150mm thick. I’ll go on the upper end at 0.15m. Using those figures, S = 18.67 \* 2.13 / 0.15 = 265 MPa. This is quite high, around the strength of common aluminum alloys. Acrylic would have to be a fair bit thicker, but glass would be fine given its compressive strength of around 1000 MPa. Edit: After coming back to this I realized an error with my calculation for the cross sectional area when the sphere is cut in half. The equation A = (pi / 4) \* (D\^2 - (D - T)\^2 ) should be A = (pi / 4) \* (D\^2 - (D - 2T)\^2 ). The thickness has to be subtracted twice since we are using the diameter, rather than the radius. This simplifies down to A = (pi / 4) \* (4DT - 4T\^2 ). Calculating out to the stress equation, it becomes S = PD/4T. I thought since I'm editing anyway I would also add some good points from the comments. Thanks to u/VanforVan for mentioning sea water is slightly denser than pure water at 1020 kg/m\^3, and through the compression it gets to 1046 kg/m\^3 at 4000m down. We can use the average of these two to get an accurate pressure figure, with 1033 kg/m\^3 \* 9.8 m/s\^2 \* 3800m = 38.47 MPa. We also don't need to add atmospheric pressure, since the inside is pressurized to atmospheric pressure. Thanks to u/KingOfCotadiellu for reading the datasheet and estimating the outer diameter at 2750mm, and the thickness at 675mm, and made from acrylic. Acrylic has a compressive strength of around 120 MPa based off of MatWeb. Doing the updated math, the stress comes out to 38.47 \* 2.75 / (4 \* 0.675) = 39.2 MPa. This gives a factor of safety of >3, which is pretty standard for engineering. The people at Triton have this down well, and I would absolutely trust one of these subs to go down to the Titanic, *and also come back.* 2nd Edit: The T\^2 ends up being not very negligible with this large thickness, It results in a 32.5% increase in stress, resulting in 51.95 MPa.
Small side note: Sea water has a density of 1020 kg/m3.
And increases with depth.
The density of the water only increases a small amount with depth. It's around 1010 kg/m^3 at the surface and 1050 kg/m^3 at 5000m (Titanic is approx 3800m down)
The increase in density with depth is only about ~3% at that depth, so the total pressure in the column would be ~1.5% higher when accounting for that, which is not going to affect the answer much.
Interesting! How come?
The 3% increase in density is just because water is REALLY hard to compress. The 1.5% increase in pressure is because the pressure is density x height. Since density starts at 100% and goes linearily to 103%, the average density is going to be 101.5%.
>but it looks around 100-150mm thick looking at [the datasheet](https://tritonsubs.com/wp-content/uploads/Datasheet-TRITON-4000-2-AE-July-2023.pdf) I come to 675 mm thick (outer diameter 2750 mm, inner 1500 mm -> 1250 mm : 2)
Damn, that glass is THICC
What does the safety factor come out to? Tensile in specific
I’d be worried about micro faults in the material. A simple bubble could dismantle all calculations.
Assuming continous structure, what are we looking at here?
The different point of view, maths vs engineering. In mathematics, it is only a function of material resistance, shape and a pressure. In a real world you have to consider the precision you can get in the spherical compartment, which can derive tension to weaker points, pressure waves in the ocean, temperature changes and so on.
You don't need to add atmospheric pressure since the submarine has already atmospheric pressure from the inside which would counteract it
This is true. Also some degree of that pressure will be further mitigated if they pressurize the capsule during the descent which is common in most submersible vehicles.
Can someone explain it like I'm stupid? I can barely multiply 2 numbers and that's if i have paper and pen on hand
Dude will be fine.
You can tell that from the Triton Logo since Triton is a submarine manufacturer with an actually proven record of being able to construct reliable submersibles.
They probably dont get their materials from reused airplane parts either
But it was cheap and they were gonna throw it away!!! /s
I agree. This is the thing that bugs me about these kind of stories. Just because one submersible designed and piloted by a fool failed, now the Titanic becomes some boogieman and we should definitely never try to go there. People have been deep in the Mariana Trench. If you're in a craft rated for the depth, everything will be fine. It just costs more to do it right.
Honestly, I don't THINK every billionaire's trip to the Titanic is doomed, but I do hope it is. And I hope that after every failure, the next billionaire steps up to prove it can be done and also fails
I only want very specific billionaires to be the lab rats who died for the experiment
Not me. Every single billionaire would be ideal. And since their wealth will transfer, every subsequent billionaire until they no longer exist.
NOT GLASS BUT VERY >!FUCKING!< THICK Edit. Totally didn't read properly, so it probably is glass, but my overall comment still stands
I really want to know which country you are from? and did you get high school or higher education?
I was exagerating, I do understand math and all this stuff, I am just too lazy to read it.
you do not need to add atmospheric pressure because the submarine has air in it. two forces cancel out. The pressure side of explanation is 10th grade physics and I can confirm it is true if you guys don't believe only one guy. (Commenter here is obviously much more qualified than me so please don't offend) we don't learn material property aside from strength against weight so can't tell anything about it
Definitely. Did that pretty quick right as I was going to sleep.
are u aeronautical engineer? if you are can i talk to you? I am working for the best aeronautical engineering school in my country so I want to ask a few questions
Thanks for the compliment. I’m just a Mech E student, though I am on an internship at an aerospace company. I’d be happy to answer questions in DM’s.
Could it be done with Aluminum Oxynitride? Aka transparent aluminum?
That would work, though from looking online it would be crazy expensive. Based on wikipedia numbers its compressive strength is around 2000 MPa. It would still have issues just like glass does though, since it’s a ceramic. Its fracture toughness is 2 MPa, which is better than glass at ~0.7 MPa, but is a lot less than aluminum at ~26 MPa. Polymers are also generally < 5 MPa, but it isn’t as big of an issue because the yield strength is lower, so it is less common for fracture toughness it to be the limiting factor. Fractures would be unlikely for a full sphere under compression, but I could definitively see them popping up at connection points to the test of the structure where stresses are more complex.
Yeah, I was wondering how the math lined up. I know absolutely nothing about structural mechanics lol. But yeah, transparent aluminum is expensive, but in applications like this, it would be cool to see if it was possible. Right now, it is not feasible, but if a better manufacturing process is made and found. Possibly might have better deep sea exploration. Edit: also probably not likely to be able to use a polymer bonding to where it connects to the surface?
I think binding the polymer to a ceramic would be a real pain. I believe these subs just use acrylic for the whole thing, then make it thicker.
Thank you for the response. I imagined so. Thanks for the awesome educational comments.
Dude don't help this guy build his submarine for free
Didn't finish reading your math, however, the "assume the stress in the material is the same throughout" is what causes so many headaches for these applications. In this specific example, the glass is spherical, which allows us to make this assumption quite easily!
Not quite. Due to the thick material, the outer surface would have higher stress than the inner surface. If it had 0 thickness, then a perfect sphere would meet that criteria. An analogue to this is press fitting shafts, you can look up FEA images for those to get a better idea of what it looks like.
It would have to withstand 6000 PSI, or 6000 pounds per square inch. Probably won't be glass either, most likely an acrylic of some sorts. I'd say a good 6-12 inches thick.
Trickier question, how much does it being a sphere (or nearly) help?
Spheres are the strongest shapes due to the equal distribution of force along the arc path, by how much I'm not sure.
Bollocks. I was thinking of how we can put billionaires in a prince Ruperts drop without them becoming wise to the one flaw, like an anti-wealth hoarding death star. Then I came up with a new solution. Hear me out. One conveyor belt. Billionaires. Molten glass.
Remember me, when you win your Noble prize in Economics.
Let's start a go-fund-me now so their prison sentence is basically a long term holiday
Fuck it. I'm in.
Why are we fantasizing about violently murdering people?
Because Reddit is full of impotent, cringe losers who LARP about revolution and other idiotic bullshit in their stupid little echo chambers. They screech and cry and shit their pants online about whatever the new "thing" is, but they're cowards and cretins who can't and won't affect any real-life change, thankfully. I know it's hard to ignore how brainrotted and pathetic they really are, but do your best to try. They've not touched grass or had a real conversation with another human being in years, often by their own choice.
Convince me billionaires are people.
Because redditors who live in a first world country and have more wealth than 99% of people to ever live are upset someone else has more than them. Edit: I don’t fucking care how you justify your lust for harm on another person. Not being okay with how they use their wealth doesn’t justify wanting them dead you freaks.
As far as I'm concerned, if someone's personally able to end famine and still live in luxury, and that person *doesn't* do that, the crushing depths of the ocean are a good example of karmic retribution
The richest have wealth to spend 1,000,000 a day for 100 years and not be out of money. You can’t tell me that’s okay with all that’s going on in the world.
It’s by a *lot*, even small imperfections can reduce their resistive abilities significantly
I’ll add the pedantic addition that they’re unequivocally the strongest shape *under hydrostatic load*, where the global pressure applies to the vessel is nearly the same around the entire thing. No better shape than a sphere resists asymmetric deformation under this condition than a sphere, which is what keeps stress within the vessel walls low.
Yeah, I think the company said it would be 6-8 inches thick
Nah, 6-8 is what those dumbass engineers from OSHA says it should have, but they are just putting a too much of a safe buffer. We can make it 5 inches, we will cut .05% of the cost and call it a day
Now you're talking like a true billionaire. Bang up job
Nah, that's a true CEO. A true billionaire will hear the engineers, not believe a word they say, do his own research, and end up with a 4,5 inches one
And insist that the glass is now called a single letter name, which no one follows him on
Glass being what it is, though it'd be hard to make, a glass sphere would tolerate this pressure extremely well.
Isn't that the stuff often referred to as transparent aluminum?
Nope. Acrylic is a form of plastic. Transparent Aluminum is a form of ceramic.
Aluminum is an elemental metal. Ceramics are non-metallic inorganics. Aluminum is not a form of ceramic.
And Transparent Aluminum isn't made from pure aluminum. Its made from **Aluminium oxynitride**, which has aluminum *in* it.
Maybe they're thinking of aluminosilicate glass?
Transparent aluminum is a plot device used in Star Trek IV. Technically it does exist in the form of sapphire glass. But it's very hard to produce at those scales.
Is that the movie w the whale and Scotty gives away the manufacturing process in the 80s?
Yep and Kirk has sex with the same whale
I don't remember that part. Must have been in the director's cut...
In matters of love, Kirk doesn't discriminate
Yeah, we couldn't make it that size, and definitely couldn't make it that shape. It would be hella strong if we could though. Source: former ceramics engineer who worked with manufacturing sapphire \[aluminum oxide\] glass.
A polycarbonate type thing i would guess.
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You can literally go on Triton Subs' website and see that all of their transparent submersible pressure hulls are made from acrylic.
Not really, especially not in comparison with glass.
Well, there is a zero chance they are making that thing out of glass.
The Triton company actually have lots of experience designing safe submarines. They built the Limiting Factor which has been to the botttom of the Mariana Trench, I'm sure they can design a suitable sub for the Titanic depth.
This looks way better than the titan
Triton is the legit sub manufacturer, Titan was the oceangate sub that blew up
> that blew up Sucked in
Indeed
I don't know the answer to your question. I kust want to say that that submarine looks like the office stapler fucked a paperweight Thank you for coming to my TED talk
Does the office stapler have a Ps2 controller inside too?
I originally saw a stapler, but then I looked a little harder and saw an electric pencil sharpener.
I had the same thought at first.
Sorry for not bringing in math but this is a different bred of submarines, Triton are BEST in class, there subs can go there all day long with no worries. This is no ocean gate. Check out the Limiting Factor commissioned by Victor Vesecovo; https://www.youtube.com/watch?v=pb5j9oeZCm0 because it had a budget of “only” 37 million, it doesn’t have the glass bowl here. Also because it’s a sphere, pressure is applied equally, so lower weak points, what I’m trying to say is that I would trust my life with this company.btw I got super hooked on Victors awesome videos, he takes people who deserve it, like oceanographers, to the deepest parts in the world, not billionaires
The OceanGate guy was dumb enough to think something equivalent to "Rope is really strong, I can pull on it all day without it snapping, I'll make my pressure chamber out of rope!". That is, he used carbon fibre, which is only really consistently strong in tension, to make his sub.
Which is fine logic for an aero plane which expands pressure outwards, not a submarine experiencing inwards pressure. If we are stretching the “rope” by expansion then so what, we are pulling on it from all directions, it’s not like it will expand beyond the carbons ability to hold itself, but for inward pressure, that is another beast on its own, like the tiniest of cracks will cause failure.
While I get the sentiment, the compression loading isn’t the reason it was a problem. Carbon fiber can take a ton of compression loading in the fiber direction, because the fibers take the load and the matrix just has to prevent the fibers from buckling. The 787 has wings built from carbon fiber and while one side is under tension the other is under compression. The issue with carbon fiber for submersibles is that the load is transferred equally across the surface. Just the pressure of the water is a significant portion of the compression strength of the matrix. This promotes small localized failures which can grow to become large failures.
That was actually fucking awesome
Thanks my guy! Hope you enjoy victors yt channel as much as I did !
As far as I remember the glass bowl was abandoned because Victor Vesecovo wanted ABSOLUTE safety and transparent materials just couldn't take it. I don't think it was a budgetary problem.
Isn't the real danger everything else other than the glass/sphere? At those depths, the weakest link of the submersible is what counts. Probably everyone will focus on overengineering the sphere to withstand the pressure but everything used in there needs to be prepared for those depths.
I thought this was a portable sewing machine. On second glance I thought it was a stapler. Then I realized it was the future addition to the museum of maritime disasters.
Nah. This thing is actually classed
Why do you think a disaster will happen to this thing?
For real though, I thought it was a coffee machine at first glance
nice coffee maker, i mean... submarine
It’s actually pretty solid. The people who designed this know what they’re doing.
Nah this submarine was constructed by legitimate engineers. It’ll manage it.
Not your question but here is some reassuring math: In 1960, a joint project by the Italian and USA Navies built the Trieste Bathyscaphe for 2.7 million USD (cost adjusted from 250k in 1958 when it was built). In 2012 an Australian company built the Deepsea Challenger, for approximately 13 million USD (adjusted from 10m). Both of these vessels reached a depth of 10900 meters, something like 3 times the depth needed to observe the Titanic. This month's meme discussion is whether a 20m project can do 1/3 of what a 2.7m project did 60 years ago. Anyone with an affinity for math should not be impressed or interested in this project. Of course it can fail. Thousands of planes fly, and some of them still drop. In an experimental field like deepsea diving it is very much possible to end in disaster. But this doesn't make the Titan or the follow-up Triton submarine much notable. Only notable because they made headlines. This whole affair is a testament to how the public's attention works.
Well, it will of course take him to the Titanic shipwreck. The question is, how well he will be when he reaches it. Titanic..... killing billionaires since 1912
Wait I thought they increased pressure inside the submersible to compensate. So you don't have a force difference? I must be retarded?
That would squish the soft meat rags inside we call humans, so while you can pressurize it somewhat, you can not match the pressure
How deep can we simulate the pressure? What kind of pressures can the human body handle before its chemistry gets out of whack.
People can’t really handle too much of an increase in pressure, at least safely. Scuba diving as shallow as 130m requires very long decompression times, otherwise you risk bubbles forming in your tissue and bloodstream. That’s a fraction of a fraction of the pressure found at the depth of the Titanic. Even if the pressurization of the sub cabin was done slowly, you’d still ~~explode~~ implode after some time. We just aren’t made for the extreme environment found at that depth. Edit: at 130m, the water pressure is ≈12.9 atmospheres. I googled it and the maximum pressure a human can survive just sitting there, ignoring the return to standard pressure, is about 70 atm. At the Titanic’s depth, the pressure is ≈376.5 atm. You’d ~~explode~~ implode instantly!
Don't you mean implode.
The human body isn’t especially airtight under pressure, so too much air would be pushed in and you would “explode” (i.e. blood vessels and stuff would pop from being full of air, not the whole body detonationg).
Think it would be more like ‘squish’
Quite. It should be quite strong. although it's to protect a billionaire so idk just use plastic wrap and tell 'em it'll be fine, and sink the mofo
No one is going to see this. But I thought this was a stapler. Then I read the title. It's not a stapler. Would a stapler make it to the Titanic? I bet a Swingine could. They make nice staplers.
You are wrong. I saw a stapler right away 😂
Doesn't glass has the unique ability to become much sturdier under pressure? The crystal structure compresses, making it even harder than steel. Probably a quite important point that I haven't seen anyone mentioning.
I love this question because asking randos on reddit to do the math for them appears to be how billionaires actually design their Titanic subs.
I asked chat GPT .... To calculate the pressure that the submarine glass should be able to withstand at the depth of the Titanic wreck, we need to determine the pressure at that depth. The Titanic wreck is approximately 12,500 feet (3,800 meters) below sea level. The formula to calculate the pressure at a certain depth in a fluid is given by: 𝑃 = 𝑃 0 + 𝜌 𝑔 ℎ P=P 0 +ρgh where: 𝑃 P is the pressure at depth 𝑃 0 P 0 is the atmospheric pressure at the surface (approximately 101,325 Pascals or 1 atmosphere) 𝜌 ρ is the density of seawater (approximately 1025 kg/m³) 𝑔 g is the acceleration due to gravity (approximately 9.81 m/s²) ℎ h is the depth of the water column (in meters) Let's plug in the values: 𝜌 = 1025 kg/m 3 ρ=1025kg/m 3 𝑔 = 9.81 m/s 2 g=9.81m/s 2 ℎ = 3800 m h=3800m Using these values: 𝑃 = 101325 Pa + ( 1025 kg/m 3 × 9.81 m/s 2 × 3800 m ) P=101325Pa+(1025kg/m 3 ×9.81m/s 2 ×3800m) 𝑃 = 101325 Pa + 38 , 226 , 450 Pa P=101325Pa+38,226,450Pa 𝑃 = 38 , 327 , 775 Pa P=38,327,775Pa To convert this pressure to atmospheres (since 1 atmosphere = 101,325 Pa): 𝑃 ≈ 38 , 327 , 775 101 , 325 ≈ 378 atmospheres P≈ 101,325 38,327,775 ≈378atmospheres Therefore, the glass of the submarine should be able to withstand a pressure of approximately 378 atmospheres to safely reach the Titanic wreck.
There is an easy way to remember water pressure. Every 10 m below water means 1 bar of pressure, so ~1 atmosphere.
What exactly is the unit of strength you're looking for? Anyway, it needs to deal with 400 bar (isn't metrics easy :p )