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A comment on After 27 years within budget Austria open 6thlongest railway tunnel in the world. Parent comment

Re:After 27 years within budget Austria open 6thlongest rail... by jimnotgym on Friday December 12, 2025 @03:15PM (#46248317)
Serious question about hyperloop trains running in a vacuum. How do you cool the carriages?
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Re:After 27 years within budget Austria open 6thlongest rail... by sawjet on Saturday December 13, 2025 @02:45AM (#46252863)
The tunnels aren't perfect vacuums
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Re:After 27 years within budget Austria open 6thlongest rail... by jimnotgym on Sunday December 14, 2025 @04:16AM (#46261834)
That doesn't help me, I'm afraid. It must be low enough pressure to allow lower air resistance on the train, so must be a significant vacuum. Even if not a perfect vacuum, the carriage can presumably not exchange air with it, since the carriage is at a higher pressure. If you used aircon in the train the lower pressure air in the tunnel would be very poor at convecting heat away?
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