The biggest problem is he’s engineering in Imperial instead of SI units.
Am I assuming correctly that we’re looking at a big succ-situation, where the diver will big forced through the tube no matter what?
It’s a difference of like 7 psi over an area of what looks like maybe 30 square inches, which would be uncomfortable to get caught in, but I don’t think you’re getting Byford Dolphined
210 lbs will certainly keep you stuck there though
Ahhh yeah that’s where I’ve heard it before, WTYP had an episode on that!
For fun you can search up Delta P to get to industrial horrors beyond comprehension
Ayyyy, a wild Well There’s Your Problem reference. By far my favourite podcast.
from a different reply I understood the meaning of the last two words: https://en.m.wikipedia.org/wiki/Byford_Dolphin
If you were on your back and had your legs above the hole, is 7 psi strong enough that you wouldn’t be able to fight it?
I guess another question would be “how strong would it be compared to gravity?” (if anybody has any idea)
It very much depends on the size of the hole. 7 psi over 1 square inch is 7 lbs, but the same pressure over 100 square inches is 700 lbs.
For a naive estimate, the hole looks around 6 inches wide, which gives it an area of around 30 square inches, so there’s like 200 lbs of water pressure over the area of the hole. An even more naive assumption is that if you were “standing” over the hole in the wall, you would feel 200 lbs of pressure forcing you “down,” which I think most people could easily handle. I’m doing more than that right now!
Unfortunately I don’t know how to even start to calculate the force of the water on you as it rushes past you, but my gut instinct is that it wouldn’t be more than the total pressure in the hole
Yup.
I don’t see the problem.
I mean, I don’t swim, but the dynamics seem to make sense.
What am I missing?
Edit: Ah, don’t go near the water passage, right?
DELTA P 🗣️🗣️
When it’s got ya, it’s got ya.
Wouldn’t this human in theory become a crumpled sausage like what happened to the crab by the leaking underwater pipe?
https://en.m.wikipedia.org/wiki/Byford_Dolphin#Diving_bell_accident
Fuck all of this
Not at 15 feet. I don’t know enough to say how fast the water would be leaving that hole, but it’s maybe a couple hundred pounds of pressure. If he even got caught, it would be super uncomfortable, but he ain’t about to get ∆p’d
If you wanna see a real crab-in-a-pipe situation, look up that Byford Dolphin everyone’s talking about
Let’s convert to metric so we can tell.
15 ft is about 5 m.
Water pressure increases by 10,000 pa per meter (rhogh, rho=1000 kg/m^3, g~10m/s^2), so total pressure is 50 kpa, or 1/2 earth atmospheric pressure.
One side of that hole has ambient pressure of 1 atm. The other side has that plus water pressure totalling 1.5 atm.
A pressure is just an energy density. Multiply by the cross-sectional area of the interface to get the energy gradient across the interface. An energy gradient is a force. We don’t have a measure of the cross-sectional area of the hole, but if we expect a person to fit through let’s call it 1m^2.
50 kpa = 50 kJ/m^3, so total force felt across this opening is 50kN which is the equivalent weight of five metric tons.
Size of the hole absolutely matters. If it’s only the size of a fist (10cm x 10cm) then instead of 5 metric tons it’s only 50 kg of equivalent weight, or about the weight of a person and easily survivable.
Let’s convert to metric so we can tell.
15 ft is about 5 m.
Water pressure increases by 10,000 pa per meter (rhogh, rho=1000 kg/m^3, g~10m/s^2), so total pressure is 50 kpa, or 1/2 earth atmospheric pressure.
This is very interesting. I like unit conversions.
What I did was just take 21-14 psi, and then converted that to bar or atm. I got a number close to ½.
I was like, half an atm? Can’t be that bad? I can handle 1 full mf atm literally all mf day mf.
But I guess that’s different somehow? I just don’t understand how yet. If anyone would care to go into it with me… 🙏
Remember a vacuum does not have suction it’s the air that presses things under vacuum together. One atm is actually quite a lot but we can withstand that as it’s pressing at us from all sides including inside.
The atmosphere is big and heavy. Small pressure changes on order 1% means hurricane. 50% of an atmosphere pushing on something is a lot.
Note, this is all Earth’s atmosphere.
Titan’s atmosphere is energy-denser than ours at 1.5 atm. Titan is Saturn’s largest moon.
Venus has 96 atm. Absolutely crushing and hard to visit at all.
Mars varies from like 0.3-0.6% seasonally as significant portions of its CO2 atmosphere deposit onto the poles as dry ice glaciers in a runaway greenhouse style. CO2 snows out, temps drop, more snows. Keeps going till the sun comes back. Sunlight sublimates the ice back into the atmosphere in a similar runaway fashion. Like a deep breath in and out with the seasons. The weight of all that ice falling and leaving keeps that red lump beating every year. Don’t believe those who say Mars is dead. We don’t know yet. Don’t count out anything with a breath and a beat. What is life on a planetary scale, anyhow?
The gas giants have atmospheric pressures so high it kind of stops making sense to use these as comparisons, and instead we have to look to geology for analogues as deep within the earth we also approach these energy densities.
Yeah I read the entire Wikipedia entry on the Byford Dolphin and I almost threw up because how vivid the description is. I think this would be my third time saying this but that’s not a nice way to go (to die) at all.
You weren’t kidding. Real horror movie shit.
You aren’t kidding that they weren’t kidding. I genuinely felt a bit of a ping of nausea and had to mentally distance myself a bit from imagining it too vividly.
I hope you’ll be able to forget, bud. ❤️
I genuinely had already forgot this and to look what you we’re concerned I’d remember.
I’ve been smoking daily for uhm, a few years now.
Top 10 ∆P incidents
Yeah I read about it. Definitely not the nicest way to go.
Do NOT put your dick or butthole there
Big ‘Guts’ vibes here
Chunky marinara factory.
Only the Byford Dolphin ruduces an entire diver to a soup-like homogenate in 30 seconds