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The Hyperloop was always a scam
(www.disconnect.blog)
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this post was submitted on 22 Dec 2023
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There wasn't going to be any air resistance. They were just going to build a vacuum chamber 1000 times larger than the biggest one ever engineered, then contain it in a thin metal tube snaking hundreds of miles across the heat of the California desert. So simple. /s
Good thing California is geological stable, otherwise it would never have worked.... /s
Right, that was the whole point. I think folks arent appreciating air resistance. The ISS is an example of what vehicles are capable of without it. Speeds incomparable to anything on earth, with little fuel usage. Its the largest source of inefficiency in travel. And the engineering science of reducing it is wholesale a scam for people.
The ISS travels at a constant speed in relation to the earth. People have to get on and off a train
Yes, acceleration is a thing, but trains a)reach a top speed and spend a lot of fuel maintaining it, and b)reaches much, much lower top speeds, with any effort to increase it requiring exponentially more fuel to reach and maintain. Air resistance is an absurdly important factor to travel efficiency.
Whoooosh
No, without air resistance , you don't get that sound.
Yeah i seen the rest of it, i was short on time. Thats not how engineering tubes works, we use them because you can add as much length as you want, the balancing of pressure forces occurs cross sectionally. A 2 foot pipe carrying 100 psi is experiencing the same stresses as a 2 mile pipe at 100 psi. You might as well be adding a /s to the idea of distributing water through pipes.
Very long pipes use expansion/contraction sections that may not be possible for a vacuum sealed system that has to be incredibly straight to allow the passage of a train, and can flex pretty significantly for earthquakes, seasonal temperature changes, etc.
Earthquakes keep getting brought up as if they're not devastating to absolutely everything we already use. What if an earthquake hits a regular train? Or a bridge, or a house. only a vacuum tube is susceptible to earthquakes.
If any part of the hundreds of miles of tube suddenly stops being a vacuum chamber, every train all along the tube is going to be hit by air rushing in, at the speed of sound, with all the turbulence that implies, while its already moving at full speed. It might be possible to engineer a capsule that will keep the people inside alive when that happens, but it is not at all the same as e.g. rail, where "stop moving fowards" depletes essentially all the energy in the system.
You deal with thermal expansion the same way you do with continuous welded rail.
The major strategy on CWR is pretensioning, but there are also multiple kinds of expansion joints used in different circumstances. I'm not saying it's impossible to do the same with a vacuum chamber, but I am saying there's no simple reliable answer, and certainly no answer so obvious and bulletproof that it doesn't even require testing before you could start construction.
Elon Musk either didn't know or didn't care that his company wasn't doing the required engineering and testing to make a real functioning hyperloop.
I think a better example is airplanes. You run at high altitudes to increase efficiency due to reduced atmosphere.