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China’s new bullet train prototype sets global speed record at 450 km/h in test run - Hindustan Times
(www.hindustantimes.com)
this post was submitted on 30 Dec 2024
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Isn't the record 600km/h?
603 for maglevs, 574.8 for steel rail, set in France in 2007 by a hotted up, modified TGV.
China holds the record for a stock train at 487, set in 2010.
(all per Wikipedia)
It looks like the article might be implying that they will be the fastest trains operating in revenue service when they enter service, but that surely needs to be demonstrated with a production train in revenue service.
...production train in revenue service over the period of usual track maintenance. It's not the rails I'm worried about but the overhead lines, have a look at the TGV record run there's a lot of arcing that can't be good for them. On the pantograph side the contacts are carbon, notoriously brittle, and generally speaking over 300km/h things become dicey just because of heat buildup. Automated retraction systems can prevent the worst, meaning the pantograph getting tangled in the lines at speed, but, well: Production revenue service. Can't have those fail-safes kick in or you'll mess up the timetable.
European high speed trains actually got slower vmax over the years for the simple reason that the rest of the systems is reaching practical limits and it doesn't make sense to have trains that can drive speeds that the track will never reasonably support. If you want to go faster you want to go contactless which means building a whole new, incompatible, network. And the only maglev system with affordable tracks, as in bucks per kilometre (TSB), has a design limit of ~200km/h: It uses bog-standard third-rail like technology for electrification, everything else would be expensive. But for its intended use-case as an S-Bahn 200km/h are plenty and you get nice bonuses such as 10% gradients and inexpensive viaducts (because no point-loads they can be built way lighter).
China, in the end, isn't that large. You can do high-speed sleeper trains, 12-14h or such, from one end of the country to another with existing stock technology, and so btw could the US.
retrofitting and hybrid operation seems possible though: https://en.wikipedia.org/wiki/Nevomo
they already built a small working prototype
I very much doubt they're doing contactless power transfer with nothing but the existing rails and overhead wire. Alsomention of "hypertube" sets of massive alarm bells.
Check out their road map and the videos of their prototypes. It is very much not a tech bro project :). The first goal isnt event maglev but magnetic propulsion.
The TSB does the same, on plain steel rails. Levitating on them, using them as what'sitcalled reaction component in linear magnetic propulsion, only the power transfer is direct contact. TSB rails may look a bit fancy but they're two electrified steel beams in concrete casing. Your Poles may be working on an improvement to linear motors but it's not a new concept. Thinking of it they should look into breaking applications: Mechanical breaking causes massive wear so fast trains are using induction brakes but those don't work to bring the train to a complete standstill, but if the brake is a linear motor it could do that. Selling magnetic brake tech to Siemens or Alstom would probably set the lot of them up for life.
The company developed TSB because they were part of the Transrapid consortium, responsible for the track, and judged that ultimately track cost was why the whole thing failed to materialise, so they sat down and said "what's the cheapest track we can build" and then designed the rest of the tech around that. Cost differs depending on lots of details but overall they're actually cheaper than standard rail, doubly so if you take lower maintenance costs into account.
Yes,
If it has an operating speed of 450km/h this would be impressive.
But just reaching this speed is far from a world record, the French TGV record from 1990 is 513km/h, it reached 574.8km/h in 2007 which is the current world record.
And they thunder around at 300-360km/h all day every day.
Wind resistance is a problem at speed which is why production trains rarely go faster. Airplanes at altitude see much less win resistance. (hyperloop would also be good but will never be reasonable to build even if the engineering challenges are overcome)
Japanese bullet trains had to get a redesign due to something akin to sonic booms when leaving tunnels that annoyed the hell out of residents several times an hour.
Noise is another issue of course but energy is what will kill faster trains for forever
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