Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

China unveils 600 kph maglev train prototype

globaltimes.cn

Post reply on HN
Print view View original

91–100 of 192 posts

Re: China unveils 600 kph maglev train prototype

#91

Post by zeristor »

adamlett wrote: post #47
zeristor wrote: post #31

At these high velocities air resistance becomes a huge problem, making it impracticable. Wasn't this the main reason for putting very fast trains through evacuated tubes, my copy of the Usborne Book of the Future had this in seventies. Although Musk had a go at reviving it, the ideas Hyperloop has been based on have been around for ages.

There's rumours of a vehicle that has somehow overcome the problem of air resistance and is able to go faster even than this train: "The Aeroplane". Maybe you've heard of it?

They also fly at altitude, where air pressure is much less obviously.

Re: China unveils 600 kph maglev train prototype

#92

Post by JoeAltmaier »

anoncake wrote: post #79
melling wrote: post #72

Earlier quoted context omitted.

Replacing 225 mph trains with 400 mph maglevs should be worth it, especially on long routes like the 800 mile trip between Shanghai and Beijing. I didn’t say it would be easy or cheap. I’m sure there are lots of details to consider. China, however, has no problem doing large infrastructure projects.

> Replacing 225 mph trains with 400 mph maglevs should be worth it, especially on long routes like the 800 mile trip between Shanghai and Beijing. That's 2h vs 3.5h, not taking into account acceleration. Time on a train can be used productively, so it isn't lost. Taking opportunity costs into account, it may or may not be worth it. I'm also not sure if 225 mph is the physical limit of conventional trains. Also, faste…

Its not just about the passenger. There have been historical increases (geometric increases) in the economy each time the speed of commerce improves. Horse (4mph) vs ox(2mph); steamship vs sail; scheduled steamship service vs sail-when-full; fixed-price postage vs line-up-at-the-post-office; transcontinental railway. Heck even FedEx was a game changer.

And its not just passengers, its cargo too. Imagine a delivery service that can offer 5 shipments a day vs 4 because the trains are faster. It has its effect on the bottom line.

Re: China unveils 600 kph maglev train prototype

#93

Post by dasKrokodil »

[deleted] wrote: post #10
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.

[deleted]

I think the main problem with the so-called high speed trains in Germany is that they don't have their own rail network, unlike the Shinkansen in Japan or the Maglev trains in China.

Re: China unveils 600 kph maglev train prototype

#94

Post by blu42 »

adamlett wrote: post #47
zeristor wrote: post #31

At these high velocities air resistance becomes a huge problem, making it impracticable. Wasn't this the main reason for putting very fast trains through evacuated tubes, my copy of the Usborne Book of the Future had this in seventies. Although Musk had a go at reviving it, the ideas Hyperloop has been based on have been around for ages.

There's rumours of a vehicle that has somehow overcome the problem of air resistance and is able to go faster even than this train: "The Aeroplane". Maybe you've heard of it?

Propeller-based airplanes are not that much faster than this train -- current propeller world record stands at 855 km/h. For higher speeds jet/turbofan engines would be the choice, as they are among the few propulsion forms that can operate very efficiently with the atmospheric medium, rather than fully against it (up to certain speeds). So unless you equip that train with jet turbines (impractical for a number of reasons), you will be paying a huge energy price for airplane speeds at ground altitudes (holds true for any kind of ground transportation). As a result those trains are seldom operated at their peak speeds.

Re: China unveils 600 kph maglev train prototype

#95

Post by mattlondon »

Jaruzel wrote: post #78
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…

Here in the UK we enjoy low speed trains every day. ;) Just seeing this stuff in other countries really makes me sad about how my countries technological developments have been left to rot.

Hmm well its not soooooo bad - 185mph/300kmh for High Speed 1 (1), with High Speed 2 (2) under construction at the moment (in some parts of the coutnry anyway) and pegged at 250mph/400kph (2).

London-Edinburgh is old and goes at about 125mph/200kmh. London-Glasgow is slightly-less old (in terms of trains) and does 120mph/225kmh).

Suburban trains are slower of course, but they stop pretty frequently anyway.

tl;dr - its not terrible. Prices are high though so flying is often orders of magnitude cheaper, even in the "door to door" time is about the same or slightly less by train.

1 - https://en.wikipedia.org/wiki/High_Speed_1 2 - https://en.wikipedia.org/wiki/High_Speed_2

Re: China unveils 600 kph maglev train prototype

#96

Post by anoncake »

mdendura wrote: post #17
[deleted] wrote: post #10

Earlier quoted context omitted.

[deleted]

But isn't that down to Deutsche Bahn having lots problems with funding, industrial action etc?

The problems with it are:

- It was split up. For example, the tracks and the rolling stock are owned by different companies. All these companies are owned by a holding and all use the DB brand, but they independently try to make a profit.

That makes sense to economists trying to let the market organize as much as possible, but not to railway employees trying to run a railway. For example: before, the Bundesbahn built its infrastructure, balancing cost vs needs. Now, the infrastructure company optimizes for its own profit and cuts corners, no matter how much the companies operating the trains have to spend to compensate.

- The government was planning to sell it on the stock market. In preparation, DB neglected its infrastructure to appear more profitable. Fortunately these plans were dropped, but the damage is done.

Another insane decision that still contributes to this neglect: Maintenance is funded by the DB. Construction is funded by the Ministry of Transportation[1]. So the DB neglects infrastructure until it has to be replaced.

- Probably the worst one: It competes with cars and trucks. The automobile industry is very powerful in Germany. Properly funding the DB would lower their profits so it doesn't happen.

[1] and Digital Infrastructure. Yes, our ministry of transportation is responsible for the information highway. I am not making this up.

Re: China unveils 600 kph maglev train prototype

#97

Post by kuschku »

88840-8855 wrote: post #76
kuschku wrote: post #33

Earlier quoted context omitted.

Most of their "world leading" High Speed Rail, as you call it, is actually using Siemens Velaro D/E rolling stock — the same train used in Europe as "ICE" or for some of the Eurostar lines :)

Siemens Velaro have gigantic issues in good old Germany. And China has indeed homegrown machines, such as the CRH380A or the CR400AF. Further, there is also a lot of shit tier technology in Germany. https://en.wikipedia.org/wiki/H-Bahn Siemens is actually still offering that system. If you ride it, you will wonder how it was possible to combine all disadvantages of all existing people mover rail technology and to pro…

> Siemens Velaro have gigantic issues in good old Germany.

I have heard about a lot of issues with many kinds of rolling stock, but so far I haven’t heard anything negative about the DB Br 407. The Br 412/812? yeah, that one’s fucked, but so far I’ve heard few complaints about the Br 407 (and personally, the Br 407 is probably the smoothest ride there is)

Could you describe some of the issues you’ve had with the ICE 3 (MS)?

Re: China unveils 600 kph maglev train prototype

#98

Post by fluffything »

melling wrote: post #46
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…

High-speed rail also works well in China. It’s the same size as the United States, which is about the size of Australia. There are only 25 million people in Australia though.

> There are only 25 million people in Australia though.

There are a "couple" more million people in France, and there are many areas in the US and Europe which much higher population than Australia, and a fraction of its size.

Re: China unveils 600 kph maglev train prototype

#99

Post by nicoburns »

SiempreViernes wrote: post #66
gnode wrote: post #29

The cabin is interesting. There doesn't seem to be much visibility through the windows. I guess at such speeds the driver can only rely on information feeds from far up ahead, and there's little advantage to being able to see with the naked eye. Large windows would probably make it less safe in the event of flying debris too. It makes me wonder why not get rid of them all together and make the cabin like a tank. To g…

That's a good point, wonder if they can even open the side windows to look out? I think the windows on trains generally serve to give situational awareness at the station, once you are up to speed reacting to unexpected impediments isn't so time critical since the train isn't likely to stop fast enough anyway.

> wonder if they can even open the side windows to look out

Almost certainly not. Open windows are terrible for aerodynamics. Even in normal cars they can cause a noticable reduction in fuel efficiency. I'd imagine the effect would be much worse at these speeds.

Re: China unveils 600 kph maglev train prototype

#100

Post by rswail »

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…

Australia is huge, but everyone lives in 7 cities (within a margin of error). A high speed rail that covered Melbourne/Albury/Canberra/Sydney/Newcastle/Tamworth?/Brisbane would have a huge impact.

The distances are (as the crow flies): Melbourne-Albury: 260km Albury-Canberra: 219km Canberra-Sydney: 247km Sydney-Newcastle: 117km Newcastle-Tamworth: 219km Tamworth-Brisbane: 450km

That last leg might need another break in it.

But at 300kph average speed that's 2.5 hours Melbourne - Sydney (CBD-CBD), say 3.5 hours with stopovers.

To get to Sydney for a 9:00 start in the CBD from Melbourne now takes (CBD - CBD): Taxi: 30m + 1hr check in + 1.5 hour flight + 30m taxi: 3.5 hours.

I'd take the train any day. Space, able to work, sleep, dining car etc. Not affected by weather or other airport backlogs. You still get up at a god-awful time of the morning, but the actual travel would be much more tolerable.

Post reply on HN