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Why are maglev trains still rare? (lemmy.ml)

submitted 1 year ago by [email protected] to c/[email protected]

142 comments fedilink hide all child comments

They were invented decades ago.

They have fewer moving parts than wheelbois.

They require less maintenance.

There's obviously some bottleneck in expanding maglev technology, but what is it?

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[–] [email protected] -1 points 1 year ago (1 children)

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.

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago) (1 children)

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.

[–] [email protected] -1 points 1 year ago (1 children)

"vacuum tube doesnt automatically mean conditions on a spacecraft in sci-fi "

Half atmosphere is less pressure difference than normal passenger planes.

[–] [email protected] 2 points 1 year ago (1 children)

The direction of pressure difference is important

[–] [email protected] -1 points 1 year ago (1 children)

Its the same? Pressurized cabin in a lower pressure environment

[–] [email protected] 1 points 1 year ago

The problem is the high pressure environment outside the low pressure environment