“It’ll be complete in 2 years”
-some idiot emerald baron 8 years ago
A very long muskrat indeed.
I think there needs to be some disambiguation.
Richard Branson’s Virgin Hyperloop One is literally a train. They themselves call it a train. I guess the idea is that they’re small individual cars (called pods) instead of a chain of train cars connected together, which seems really energy inefficient.
Elon Musk’s Hyperloop is a train for automobiles, which has all the inefficient downsides of a personal car, with none of the energy benefits of a train. It is the worst of both worlds. And it relies on car infrastructure at both ends, so it will bottleneck just like a highway on/off ramp. Completely nonsensical.
That sounds like a very Muskrat idea. Don’t worry though, he never builds his own ideas. When someone smarter comes along and invents something better, Elongated will buy it and claim to have invented it, just like every single one of his other accomplishments.
Elongated 😂
Musk “invented” the hyperloop and said he didn’t want to develop it and others should. One of the companies that picked it up was virgin. The car tunnels are the “loop”.
Structurally it also falls through, it just can’t happen
Leave it to Musk to be so full of himself that he thinks he’s invented trains.
The Hyperloop is just a fancy train. Or a very large vacuum tube document transfer system, whichever description you like best.
So I have a question for anyone who might know.
Is there any reason to go with low-pressure tunnels at all? For example, having a plexiglass tunnel at .5 atm doesn’t sound that dangerous to me, and it should be easier to build and maintain, but does it actually provide any irl benefit? Like what’s the production costs/train speed/energy savings relation here? What’s the highest low pressure that starts to make sense? Like, do you have to go down to .01 atm, or can .1 or .5 provide enough of a benefit? If not now, what kind of material advances might help?
Just curious about long-term feasibility of that whole thing.
Hi, aerospace engineer here. As far as benefits go it depends.
If we assume the tube is constant volume and constant temperature. The ideal gas law says that in this case, the pressure would change proportionally with density. So if you lower the pressure by 50% the density should lower by about 50%.
Drag force is also proportional to density. So a 50% decrease in density will result in a 50% decrease in drag. This is true for subsonic speeds. The speed of sound is 343 m/s or 770 mph.
Drag also has a square relationship with velocity. So drag gets extremely high when there is an increase in velocity.
If we take the speed of the shinkansen(90 m/s or 200mph) as a baseline and lower the pressure by half. The new speed the Hyperloop would be able to travel with the new speed is 127m/s or 284 mph. That is faster 40% for the same amount the trains will have to work, but to build all of that infrastructure, spend all the money creating a lower pressure environment and maintain that pressure for thousands of miles is just not worth it. The vacuum tube is just not practical to make.
Edit: If you maintain a reduced pressure and increase speeds about 30% of the speed of sound, the subsonic equations I used start to be less accurate. But in that case drag increases dramatically in transonic and supersonic regimes.
This is the kind of actual discussion that I hope for in these discussions. While many people focus on the dangers of the vacuum tube proposed for the Hyperloop infrastructure, I always wondered about the benefits. It’s not like putting a train in a vacuum will suddenly make it go infinitely fast.
So, the question is how much faster would it go? Once you have that number, you can adjust the car vs plane vs train chart that CityNerd showed off. All it would do is deepen and lengthen the railed transit curve some amount. It would potentially increase the distance two cities could be and still provide a benefit over airplane travel. It’s just a question of how many city pairs it would help to include as a rail option.
Going from 200 mph to 284 mph won’t make that much of a difference. Yes, it’ll open up more city pairs for high speed rail, but when comparing those benefits against the cost of the massive tube construction it’s not going to seriously pencil out as a net benefit.
Here’s the video where CityNerd lays out their reasoning and charts a rough model of where high speed rail is going to be a more reasonable choice for travel based on the distance needed to go: https://youtu.be/pwgZfZxzuQU?t=477
@azimir @Erismi14 I’d be interested in seeing “the cost of building a massive tube” compared to “the cost of building a massive highway”.
DOTs across the country have been using phony math to justify ludicrously expensive highway projects for decades – given a train in a tube would be higher speed and higher throughout, I feel like using their same logic we’d see huge “economic benefits” from connecting two new business centers with a transport mode that allows workers to work in-transit.
I think if we had an economy already built around these tubes it would be much cheaper, but I think that it would still be similar if not more in price as the building of highways.
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It is not as easy as building a "bigger oil pipeline and running trains through it. The train moving at high speeds will need a complex and robust system that is continuous inside and outside the tube. The tube will also need ground foundation to handle those forces.
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Curves and elevation changes will need to happen at even flatter grades than highways. The higher speeds mean higher acceleration around curves or up inclines. The less sharp turns means more of a reliance on raised structures and tunneling. Good luck on convincing thousands of farmers to put a tube through their property
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Maintenance. A highway with a crack in it still works. A highway with a pothole in it still works. Maintenance on that pothole costs $10k USD and the highway is still usable through maintenance. Hyperloop maintenance would not be as cheap, the tube would be shut down before and during maintenance due to repressuring. The tube would need to be vacuumed again.
I’m sure there are other things undiscovered that would be costs as well.
I think the Hyperloop is a cool and shiny idea. In the US I would much prefer reliable and cheap, normal speed rail first, then highspeed, then Hyperloop if we ever get there. I don’t think we should be able to eat our pudding before we eat our meat if that makes sense.
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I think if they are doing a vacuum tube, they should get as close to a vacuum as possible.
I think if the USA is going to spend trillions on rail infrastructure, I think we should start with doubling or tripling the amount of trains on Amtrak first. It’s not as sexy as the Hyperloop, but it would get people riding trains more often
I think it will depend on future technology and that it is not feasible nor cost effective with current technology (or it would be built already).
This. Hyperloop or whatever isn’t a POC or an actual product. Meanwhile, we have actual high-speed trains in production.
Having a consistent pressure (fully tunnel or fully open air) might help, as the shinkansen needs the very long-nosed trains to help with the ‘pop’ entering or leaving a tunnel.
However that could also be alleviated with the concrete tubes at the end of each tunnel that gradually get more enclosed
The Hyperloop was never meant to be built. Elon Musk admitted it was all about fueling opposition to California’s high-speed rail project so it would get canceled. He never planned to improve transportation;
he just wants to keep people trapped in cars.
It’s basically much more expensive slightly faster trains right?
More like a pipe dream with no practical thought put into it that was sold by a conman entirely to derail the planned high speed rail that would have connected SoCal to Seattle.
The end result is a tiny quarter mile tube in a convention centre where you can drive your Tesla in a loop but only like 10 mph and god forbid there’s an emergency like a fire because there’s no emergency exits if you’re stuck behind a burning Tesla.
FWIW the hyperloop (“pods” in vacuum tubes) and the loop (teslas in tunnels) are separate grifts.
you can drive your Tesla
Incorrect. You don’t even get to drive your own car. Someone else drives a Tesla for you. Basically an underground Uber car.
And underground taxi with only one destination option. It defeats the purpose of using individual cars for travel in almost every category.
Actually, maglev trains are slowly becoming practical, and the hyperloop is just a train in a tube with no air. It won’t be something revolutionary, just an even faster high speed train. Of course removing air from a tunnel creates its own problems: What if there is a fire? Normally you could get out into the tunnel, can’t do that with no air.
It is much harder for fire to exist without air. There are some self oxidizing fires, but it should be relatively easy to avoid those materials. For fires inside the vehicle, there are some existing fire protection protocols that could be followed. There have been fires on the International Space Station and they couldn’t exactly run outside either.
The ISS isn’t exactly mass transit. In most of those fires, they could evacuate to another area if necessary. That doesn’t work for a train where basically all the space is announced for.
Having multiple, semisolated compartments in a Hyperloop train is entirely reasonable. There’s definitely room in a traincar for the occupants of a compartment that’s on fire to move to another compartment for emergency purposes.
Evacuation points would be defined every so often (say every few miles) such that the train could come to an emergency stop within one, seal doors on each side and let air in. This would take a few minutes, but so does landing a plane or stopping a high speed train.
Bottom line is that fire safety is, to me at least, an entirely solvable problem. The biggest problem with Hyperloop, I think, is that given the materials for the vacuum sealed tube and the energy required to hold that vacuum, it is just so unlikely to be more efficient than a maglev. For medium distance travel, even standard high speed rail is good enough to replace planes, so we don’t need the extra speed for ~500 mile distances. For longer distances where high speed rail is super slow or impossible, such as across continents and oceans the cost of building the vacuum tube will be so costly that it would take something like a complete ban of non-renewable fuels in aircraft for it to be a consideration. Even then, I think it could end up being cheaper to develop and use renewable fuels for aircraft.
Much more expensive? Have you looked at how much it costs to build subways in the US compared to EU? It’s absolutely insane. We are failing to do this affordably. https://www.npr.org/2023/06/26/1184420745/why-building-public-transit-in-the-us-costs-so-much
I thought it was a giant underground highway with no rest stops or ways to get out.
You left out less safe, smaller, and harder to repair
Isn’t Hyperloop just a concept for a vacuum train though? That literally is a form of train, just one that is, at least presently, too impractical and expensive to actually use. Honestly I think the concept has some merits, we just don’t have the technology, logistics or need to have use of it just yet.
I’m thinking ever. The Hyperloop was Musk’s way to disrupt high speed rail, which exists and is proven, to sell more EVs.
The vision seems like an exclusive tunnel for Tesla owners rather than a viable form of transport. Actually, I’m not really sure what it is anymore, since there appeared to be a weird one that was basically a Tesla tunnel, and another that had maglev capsules or something. Not sure either seems like the best idea ever, but I doubt decent trains will ever exist in the US, so perhaps it’s better than nothing.
I saw a video of the hyperloop… I think the convention center segment in vegas?
I’d be more comfortable burried alive in a coffin, than in that claustrophobic hell hole.
Lol what a clown
Being more environmentally friendly and cheaper? Where is he pulling that from?
Inventing a new technology from more or less scratch will be way more expensive. And I feel like they’d be comparable environmentally if they are both electric
Eh I wouldn’t think about it to much, dude is either fucked in the head, gets paid for such opinions or both.
Edit. If you’re interested in the Thai opposition, this channel has some critical vidos of it.
He uses his influence to steer industries in the direction he wants. Something that looks stupid, usually means there’s some ulterior motive. Like how Hyperloop was used to hurt high-speed rail because he could sell more cars.
Twitter, I’m not sure, I’m hoping that was something out of vanity that crashes and burns.
In the US, for Elon it was probably a smart move.
But it in Thailand you might as well advocate against the building of a new hospital because what we need is med beds from the movie Elysium!!
Hyperloop is the future, permanently.
