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China unveils 600 kph maglev train prototype

globaltimes.cn

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Re: China unveils 600 kph maglev train prototype

#181

Post by anoncake »

fanf2 wrote: post #162
anoncake wrote: post #136

Earlier quoted context omitted.

Building a railway from coast to coast has already been done in the 19th century. An HSR line is just a railway line built to higher standards: - larger curve radiuses (spelling?). Not much of a factor when a line mostly crosses sparsely populated, flat areas. - less steep inclines (but if a steam engine can climb an incline, so should every modern train) - Switches that allow high speeds on the diverging branch. But…

High speed lines can have steeper profiles than normal lines because the greater kinetic energy and loco power makes them less troubled by slopes. Eg this compares the profiles of the old Paris-Lyon route with LGV Sud-Est: http://www.railfaneurope.net/tgv/images/misc/profilln1.jpg

Even better. Though this particular example compares the difference between a general-purpose railway line designed for steam traction and a passenger line for electric ones.

Re: China unveils 600 kph maglev train prototype

#182

Post by imtringued »

Symbiote wrote: post #140
NickNameNick wrote: post #70

Earlier quoted context omitted.

I have never seen 'mts' used before, why would you, when 'm' is both more concise, and more correct? I may have seen 'gms', but I can't think when. I have seen kmph before, but not for several years. 'Kph' it's definitely current in spoken language, but increasingly rare in written form.

> I have never seen 'mts' used before, why would you, when 'm' is both more concise, and more correct? I don't know, but it's particularly common with construction materials. You can search "mts" and see many sites using the abbreviation.

I don't get it. 'm' is already as short as it gets. Why invent your own short-hand?

Re: China unveils 600 kph maglev train prototype

#183

Post by konspence »

lostmsu wrote: post #144
dis-sys wrote: post #59

Earlier quoted context omitted.

The Beijing-Shanghai line was designed to operate at 350km/h with the plan to upgrade to 380km/h, it was downgraded to 300km/h after the 2011 Wenzhou accident in which 40 people killed.

In WA we recently had a deadly accident at under 100kph...

That was ~125 km/h (78 mph)

https://www.ntsb.gov/investigations/AccidentReports/Pages/RR...

Re: China unveils 600 kph maglev train prototype

#184

Post by marmaduke »

athenot wrote: post #51

The article mentions "designed top speed of 600 km per hour". But then a bit further it mentions "Now the prototype has achieved static levitation and is in good condition" (emphasis mine). That leaves me wondering what was the actual speed reached during testing and what will be the actual operational speed. Don't get me wrong, I still find this project impressive. But there's a fair amount of boasting going on as w…

But when you see how engineering works, isn’t it reassuring to ride something designed for a maximum of 600 at a speed of 320?

My car could probably hit 160+ but I don’t drive it over 130.

Re: China unveils 600 kph maglev train prototype

#185

Post by seanmcdirmid »

_nosaj wrote: post #178
gnode wrote: post #163

Earlier quoted context omitted.

I don't think any of these things are reasons to have the driver on the train. The train drivers could be located at a remote location and still be aware of these things. Loss of connectivity already means it's unsafe for the train to continue and must stop, as it cannot be aware of signals or hazards ahead. As far as foreign objects or track failures go, these are not promptly apparent from the cabin anyway. CCTV on…

> CCTV on the track and crossings ahead is better placed for early warning. That's a lot of CCTV to replace one human.

CCTVs are cheap and have other benefits for being there.

Re: China unveils 600 kph maglev train prototype

#186

Post by the8472 »

athenot wrote: post #51

The article mentions "designed top speed of 600 km per hour". But then a bit further it mentions "Now the prototype has achieved static levitation and is in good condition" (emphasis mine). That leaves me wondering what was the actual speed reached during testing and what will be the actual operational speed. Don't get me wrong, I still find this project impressive. But there's a fair amount of boasting going on as w…

This is fairly normal for all kinds of high speed trains. Or vehicles in general. Or technology in general. Most things are not operated at the edges of their performance envelope.

Re: China unveils 600 kph maglev train prototype

#187

Post by seanmcdirmid »

GorgeRonde wrote: post #11
tty2300 wrote: post #2

I really wish we had high speed rail in Australia. I'd pick a 600km/h train over a plane any day.

High speed train works well in France (and it's just 300km/h) because the country is small. Australia is huge. And so is the US. This would make sense along coasts though but you wouldn't be able to cross the country from sea to sea in a few hours of course. What's good with trains is that you can hop in at the very last moment (when the bell rings, happened to me a couple times) and the train stops in the center of…

The biggest issue for HSR is straightened track, which should be possible in Australia as far as I can tell: not many mountains, kind of empty between cities.

This is also why’s hSR is so that impressive in China, they had none of those advantages sand had to keep blasting through mountains.

Re: China unveils 600 kph maglev train prototype

#188

Post by seanmcdirmid »

anoncake wrote: post #124
GorgeRonde wrote: post #11

Earlier quoted context omitted.

High speed train works well in France (and it's just 300km/h) because the country is small. Australia is huge. And so is the US. This would make sense along coasts though but you wouldn't be able to cross the country from sea to sea in a few hours of course. What's good with trains is that you can hop in at the very last moment (when the bell rings, happened to me a couple times) and the train stops in the center of…

> For instance the TGV has to slow down when entering cities (because of the noise) and at some point in the development of the high speed rail network, it might become more interesting to dig long tunnels under cities for these trains rather than increasing the train's maximum speed. It has to slow down anyway if it wants to stop.

You could lose a car on the back for departing passengers and pick one up on the front for embarking one’s. Only a bit of loss in kinetic energy needed (to slow down the last car and get the first car up to speed).

Re: China unveils 600 kph maglev train prototype

#189

Post by seanmcdirmid »

makomk wrote: post #113
GorgeRonde wrote: post #11

Earlier quoted context omitted.

High speed train works well in France (and it's just 300km/h) because the country is small. Australia is huge. And so is the US. This would make sense along coasts though but you wouldn't be able to cross the country from sea to sea in a few hours of course. What's good with trains is that you can hop in at the very last moment (when the bell rings, happened to me a couple times) and the train stops in the center of…

Note that, as I understand it, the security checks and queues for Chinese high-speed trains are comparable to those required at airports elsewhere if not worse.

Not really. It’s basically a metal detector conveyer belt out front with very little flow control, fast to get through and not much thought going into finding anything. Compared to airport security, it’s a breeze (but it might have changed since 2016?).

Re: China unveils 600 kph maglev train prototype

#190

Post by dredmorbius »

vonmoltke wrote: post #157
kuzehanka wrote: post #150

Earlier quoted context omitted.

That 30% rounding error are people who don't have any interest in travelling to major cities. Giving mobility to those people would unlock new use cases of its own, but the GP post is actually accurate to commercial reality.

Perth doesn't count as a major city? (% of that 30% live within its metro area. This isn't to say the 7-city grid is a bad idea, but your statement is inaccurate.

Perth (and Darwin) are essentally islands of their own.

Perth-Adelaide (nearest major metro) is 2,131km air mles, over the Great Austrailian Bight (ocean). Land route is 2,695 km (1,675 mi).

Darwin-Brisbane is even further: 2,848 km by air, 3,425 km by ground (2,128 mi).

By 300 kph HSR, those are 7+ hour trips, vs about 3 by air. And those are nearest-nighbour trips.

There is effectively no population between either location -- unless somehow induced (a possibility), a high-speed rail service would have tpo rely on endpoint-traffic only. Climate, economy, and ag productivity (low) make development unlikely.

https://www.distancecalculator.net/from-perth-to-adelaide

https://www.distancecalculator.net/from-brisbane-to-darwin

By contrast, the southeastern zone of Adelaide-Melbourne-Canberra-Sydny-Brisbane, is compact with five major metros over 1,601 km (air), though the ground route is still 2,005 km (1,246 mi).

https://www.distancecalculator.net/from-adelaide-to-brisbane

And still, the only HSR corridor that's been seriously considered is SydneyMelbourne. Quite validly.

Australia is almost wholly empty space.

https://www.openstreetmap.org/#map=5/-24.921/134.272

Populations:

Perth: 2m

Adelaide: 1.7m

Melbourne: 5m

Canberra: 0.4m

Sydney: 5.2m

Brisbane: 3.6m (metro area)

Darwin: 0.1m

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