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Why are maglev trains still rare?
(lemmy.ml)
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this post was submitted on 08 Sep 2023
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Asklemmy
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You mean that hyper idiotic Hyperloop idea that’s just a warmed up remix of the vacuum train idea from the 1920s and will efficiently kill all passengers if a little thing goes wrong (if you can get a hundreds of kilometres long vacuum chamber airtight anyway)?
its a big topic, just be aware that "vacuum" in the real world is a sliding scale of air pressure. vacuum tube doesnt automatically mean conditions on a spacecraft in sci-fi when a hole is shot through a window. You can cut air pressure to half of atmospheric, and have an extremely weak vacuum, and still get amazing efficiency gains. We already have routine transit of pressurized cabins in the form of planes.
Still means 0.5 bar overpressure if something breaks, which is deadly. Also the proposed pressure for the Hyperloop was 0.1 atmospheres iirc. If there is a weakness in the tube it will fail catastrophically and a pressure wave kills anyone in it. Watch the video where the mythbusters implode that huge tank.
You basically bring a lot of the problems with space travel down to earth.
"vacuum tube doesnt automatically mean conditions on a spacecraft in sci-fi "
Half atmosphere is less pressure difference than normal passenger planes.
The direction of pressure difference is important
Its the same? Pressurized cabin in a lower pressure environment
The problem is the high pressure environment outside the low pressure environment