Japan showcases really, really fast … whoa, WTF was that?! For the second time in a week, Japan has smashed speed records, showcasing a really, really fast train outside Tokyo on Tuesday. The maglev monster managed to hit 603KPH (375MPH) on a test track close to Mount Fuji, beating a record it set just days earlier with a run reaching 581km/h. The seven-car Lo Series carried 49 …
I've always thought that maglev is the way to go, and it seems both the Japanese and Elon Musk agree.
If the mag-rail-thingy is raised on stilts it will cope with undulating land, won't have any problems with wandering animals/people, won't split farms in two, won't be subject to flooding, etc.
"One small issue with Maglev: Cost of infrastructure."
Which means it's not guaranteed in Japan. Much of the bullet train network (btw great trains to ride on) was built on the back of corruption scandals and partly caused the big Japanese financial crash in the 1980s, the after shocks of which are still being felt over 30 years later.
Trains on stilts are still subject to flooding, even if they are completely enclosed, as their foundations may be undercut by erosion. Traditional railways currently have service cars to check the safety of their infrastructure. I have no idea what is involved in similar efforts for maglev trains, but they have been around long enough that there is certainly an equivalent for them.
Trains on stilts are still subject to flooding, even if they are completely enclosed, as their foundations may be undercut by erosion.
Just anchor to the substrate instead of the outer litho...
Wait, wait... this isn't the Culture and Earth isn't an Orbital. Too many Iian M. Banks books floating round in my head.
You're not completely off. Hyperloop is a *partial* maglev.
For a "full" maglev like this, track costs are ginormious because every inch of the track has a built-in linear motor.
The genius (or at least innovative idea) of Hyperloop is that it only has a maglev at certain boost points. At these points, the capsules accelerate, then they coast inbetween. This dramatically cuts the cost of the track. (Although the economics are still out on the details.)
Another issue at speeds like these is noise. People complain when a German ICE goes by at 250 kph. Not just the track noise, but the noise of the displaced mass of air can be substantial. This beast may have a better profile, but at more than twice the speed it will have a much worse sound profile.
This becomes less of an issue if the train is in a tube or tunnel (the proposed track between Tokyo and Nagoya is 80% underground!), but that again has sigificant cost.
I'll still line up for a ride in 2027!
This becomes less of an issue if the train is in a tube or tunnel (the proposed track between Tokyo and Nagoya is 80% underground!)
They should dig it all the way, and also evacuate (as far as practical) the air from the tunnel. That would allow it to go even faster (1000km/h ?).
No, (c) 1935 Bernhard Kellermann while Harry was but a boy :-)
Download from The Internet Archive
This post has been deleted by its author
Shinkansens are fast because the J-Gov spent beellions constructing dead straight tracks through all sort of terrain, thus saddling the country with massive debt. In Japan, the construction and concrete industries rules the roost. That's why almost every riverbank is concreted... it gives the constuction companies something to do in slack periods.
The riverbanks are concreted because almost all of the major metropolitan areas sit on the flat costal plains. The massive mountain ranges and their associated melt-water, tropical typhoons and so on generate what is known as "lots of water" and that needs directing so that it doesn't flood all over the place. Obviously this is crazy foreign behaviour to us here in the UK where we much prefer to let everything get waist deep in kak.
This theory most certainly does not explain why every river is concreted, completely destroying any semblance of natural beauty. Take the river flowing through Kyoto. It's an enormous, concrete culvert disfiguring the town. It has the tiniest trickle of water 'flowing' through it.
I used to live in sleepy Gunma near a sleepy river that has never flooded in living memory. Yet the banks of this rural river were concreted a few decades ago, and what was a beautiful resource for population is now and ugly, stagnant monstrosity.
Read 'Dogs and Demons', or just have a quick look at this guy's blog http://joshnjaxnjapan.blogspot.co.uk/2010/03/concrete-rivers-of-japan.html
... and this article demonstrates how concreting rivers has *increased* flow and flood risk (the original motivation to concrete them having been simply for the sake of it.)
http://www.nytimes.com/2007/11/07/world/asia/07iht-07japan.8224900.html?_r=0
And besides, even if *some* rivers do have to be controlled, there are other ways to do it other than smothering them with concrete, as the Jubilee River demonstrates.
http://www.japantimes.co.jp/life/2008/07/02/environment/the-right-way-to-reconstruct-rivers/
PLUS concreting the hundreds of small streams that criss cross the countryside, producing deep culverts, has killed dozens of small children over the last few years who fall in and can't climb out. It's madness, and it's madness to try to defend the Japanese frenzy for covering their country in concrete.
I had a splendid evening watching the blood moon/eclipse thing in that very same culvert in Kyoto with live music, good food and a couple of hundred friendly locals and, if I'm honest, failed utterly to see what the problem with it was. I mean, don't get me wrong, your anecdotal evidence for *every* river being concreted is hugely compelling but, eh. Seems to me like you've got an axe to grind.
As for things not flooding in living memory, I'm pretty sure that was the case for Boscastle right up until it did flood in living memory and everyone had a bad time. I mean, I take your point to an extent, just not dialled up to 11.
What axe could I possibly have to grind? Although that fact that Japan is buried is concrete is most definitely as a result of axe-grinding by the construction industry, politicians and yaks.
I too have been in a similar bar on the Kyoto river front and I thought "what a beautiful place, what a fantastic time, but wouldn't it be wonderful if the river was like it was 50 years ago rather than a dirty concrete culvert almost devoid of water?"
And in any case, there's no *need* to concrete the river in Kyoto because the water flow was 'fixed' by damning up river... that's why there's nothing but a meandering trickle where there was once a beautiful river.
If you live in a place you begin to care about it. It's an aesthetic tragedy that so much of Japan is buried under concrete. What were once beautiful rivers and streams are now just stagnant, sewer-like eyesores. A bit like this mad new plan to build an enormous concrete tsunami wall on the coast rather than try more ecologically sound ideas and effective such as creating a defence from trees and landscaping.
Ok, I get it, you don't like the aesthetics. I mean sure, Kyoto saw flooding in 2013 that the concrete culvert helped contain the worst of but whatever, right?. I mean, I love the country, too. I think it's great, but here's that same trickle in 2013 when they put out the evacuation orders. http://regex.info/i/JF4_039227.jpg I'm just sayin'
Actually, concreting rivers make flooding much, much worse (see what just happened in Japan). In the Netherlands, where the entire country is on a flood plain, they are actively removing concrete (to the point of relocating entire villages) to prevent this from getting worse (cf Room for the River).
Guy got caught by his necktie and dragged far enough to kill him. Happened some years ago, so I'm a bit fuzzy on the details, but I think he stepped off the train to use his mobile phone at a station, and then got caught in the door as he tried to get back on board.
There is also this story from about two years ago, though I don't even remember it.
http://www.cnc-communications.com/first-fatal-shinkansen-accident/
This post has been deleted by its author
Yes, I've sat through a few talks from Japan Rail, there are no accidents, so long as you count them exactly the right way. However it's still quite impressive - there's not been any deaths that can legally be blamed on them - no train crashes or such like.
Oh and I agree the Japanese have phones on trains sorted: you're not allowed to use them. Playing games (on silent) is ok and popular, but talking on the phone is not.
The entry/exit door areas at the end of shinkansen carriages are where folks go to to make and receive calls on their mobiles. There's a sliding door between that area and the rest of the carriage to keep the noise down. Loud ringtones get the Silent Walk Of Shame treatment as the offending salaryman scuttles off to the end of the car to deal with his call.
The really weird thing in some shinkansen trains is the smoker's aquarium room, a glassed-off compartment filled with grey smoke and (presumably, it's difficult to make out sometimes) people puffing away on their cancer sticks.
If it was NHK it was probably suggesting that (for example) grinding wheels to reduce friction is 'unique' to Japan. The basic fact is that Shinkansen lines are dead straight, which is why the trains can go so fast. Good old concrete and dynamiting tunnels through mountains at fantastic cost gave Japan this 'technological marvel' (although the shapes of the train noses are innovative, to reduce turbulence on entering those hundreds of tunnels.) Lots of other countries envy them, but nobody wants to pay for them.
Hi, Adam 1: I haven't heard ten centimeters referred to as "excessive" before, but I digress.
My /guess/ is that this would be enough fudge factor to allow the train to slip over irregularities in track "levelness" without disruption, but I too would like to hear from someone who knows this stuff.
This quote from How Stuff Works (http://science.howstuffworks.com/transport/engines-equipment/maglev-train2.htm) suggests a valid reason for the 10cm gap:
"A greater gap above the track means that the train would not require complex sensing systems to maintain stability."
It also notes that the Japanese design has rubber wheels so that if a power failure occurs the train simply slows down on wheels.
"There is also probably an aerodynamic effect that they are trying to avoid/exploit.
Ground effect lift maybe - makes the mag bit of the lev do a little less work.
Or maybe it just reduces drag by allowing an actual amount of air in there?"
It might be to eliminate boundary layer effects, a layer of turbulent slow moving air that increases drag. If the boundary layer interacted with the track bed the drag would be much higher. 10cm still sounds like quite a lot for that, so perhaps they're accounting for the train moving around a bit too.
<Amateur aerodynamics talk>
Boundary layers are a problem in jet engine intakes; sometimes they have slots specifically to scoop out this layer of air from the bulk flow, improves the efficiency of the intake.
Boundary layers are also the reason why small jet engines are inefficient, so a Rolls Royce chap once told me. The length of the compressor blades are shorter towards the high pressure end of the compressor, so the space through which the air flows is smaller. Stands to reason, it's a compressor; the volume has to get smaller! Anyway, what matters is the compression ratio, the higher the better.
In a small engine achieving a high ratio means that the spaces at the end of the compressor are tiny, and there is room only for the boundary flow, not laminar flow. The result is that the high pressure end of the compressor is working in slow, turbulent, sticky air. That takes a lot of engergy to overcome, which ultimately comes at the expense of thrust and fuel efficiency.
In a large engine it's less of a problem. To achieve the same pressure ratio the spaces at the end of the compressor are still a reasonable size, so there's still a reasonable amount of laminar flow. Proportionally less energy is lost to draggy air flow, which results in more thrust / better fuel efficiency. With jet engines, bigger is definitely better.
Incidentally, a feature or Rolls Royce engines compared to General Electric's is that RR's three axle engines allow them to have a more efficient less complicated compressor, and can achieve a higher pressure ratio. This allows them to make better use of the fuel burnt. An ideal compressor is one where each stage of blades is spinning at an optimum speed for that stage. No one can make one of those, but RR's three axles gives them a better approximation to it than GE's two. However GE with their carbon fibre fan blades can AFAIK make them a more ideal shape than RR's titanium blades, so get something back there. The competing design choices in large turbofan engines are fascinating!
</Amateur aerodynamics talk>
>I haven't heard ten centimeters referred to as "excessive" before, but I digress
From my understanding the force required follows an inverse cubed relationship. So it is 8 times less energy to pick 5cm or 64 times more energy than an inch.
I am sure that there is a good reason to elevate it so high, just curious.
proposing a high-speed link between America's capital and New York City. Were that to happen it would reduce current travel time from about four hours to under an hour
But given the nature of the US politics, etc. there's a couple of problems:
1) Land costs would be out of this world. The east coast is heavily built up and there's a lot of prime real estate on anything approaching a direct route from DC to New York.
2) Every politician would immediately start squabbling over where it would run, who would be in charge, and adding stops, etc. for pork barrel projects.
3) This same group would also mire it down in "safety regs" and testing and making sure the public couldn't wander onto the roadway/track.
4) Oh yes environmental impact statements including any wetlands, etc. And the added impact of additional power generation.
4) Depending on who got the various contracts, cost overruns would be horrendous.
5) Lastly, the trip might take an hour but Homeland Security would want to be involved so add at least 1 hour or more for "security screening".
If the damn bureaucrats and politicians could see fit to keep the lawyers out of it and their own selfish interests out, it might just have a chance.
Making sure that people can't wander onto the track is a bad thing? I know someone who sat through probably six hours of delays following on two suicides between Aberdeen and Wilmington. And you may remember the disaster of some months ago on the Metro North line above New York, where a woman trying to beat the gates got herself killed, along with a few commuters.
To create a new right of way between Washington and New York would require massive use of eminent domain, which can be a touchy political matter. Even with the leanest construction budget it would be quite expensive, with the money coming largely from appropriations. It would probably not be practical to have such a train stop anywhere but at the current Metroliner stops, and maybe not all of them. So if I live in Aberdeen and have my commute disrupted for years so that I can some day drive an hour and a half into Baltimore and save a couple of hours train time to New York, I might not see the benefit.
Yes, I guess it could get political.
Yeah, and leaves on the line will still be the excuse...
Nothing to do with the mish-mash collection of ownerships of the track, stations, points, junctions, tunnels, trains, delayed inadequate overrunning maintenance, piss poor tracks, inability to competently schedule to less that half hour accuracy, incompetent management. No. It'll be leaves.
What happens when you cut the current, does this thing just drop down to the ground (10cm drop), start to slide and then quickly issue prayer books....because at 600Kph there will be lot of sparks, stained underpants and prayers that the slippery path is obstacle free.
Prayers won't make the damned bit of difference but lot's of people will like to believe at that precise moment that something or someone will save them from their slippery end.
This post has been deleted by its author
already been mentioned in the other comments that the train also has wheels under it that it can decelerate on if needed, I would also imagine that given the speed and the airflow under the train that it wouldn't just drop the 10cm instantly but rather drop slowly as the train lost speed through air resistance.
probably the only time when the train is totally supported by maglev would be when it is accelerating away from a station, once up to speed I would think that the majority of lifting power would be coming from air between the track and train
"What happens when you cut the current, does this thing just drop down to the ground"
No, it doesn't, it's still levitating thanks to the perma-magnets in the track and on board, allowing the train to keep flying while at speed. Wind resistance slows the train, and eventually it settles on the wheels that it still has.
Powerless, a maglev can't brake, so overshooting becomes an issue. But you can solve that with some batteries on board to help with an emergency brake.
I always assumed that our slow UK train speeds with frequent unexpected stops, cancellations and breakdowns was deliberately designed to allow us to better enjoy the beautiful countryside we have around the railways and to give us a longer, more relaxed shopping experience at stations.
"only 28.2kph faster than the record held by a French TGV"
Either way, the power demands of rail or maglev at high speeds is immense. The world record TGV was deploying about 20MW (the fat end of 30,000 hp), and for a shortened configuration IIRC.
Whilst these very high speeds approach the speed of short haul air, you also get close to the energy use per passenger km, and you need a "runway" that extends from start point to destination.
The French steel-wheel speed record was achieved with a special "racecar" train set and it ripped up the track ballast and damaged the overhead as it passed. In comparison the Japanese maglev record train was unmodified from the trains that have been carrying out test runs for the past few years and it didn't damage the track while carrying over fifty passengers.
The same train raised the record from 581 km/h to just over 590 km/h last week, this week it got over 600 km/h. It looks like the maglev people are planning to raise the train's speed in 10 km/h steps until they can't go any further for some reason -- aerodynamics, instability, whatever. I've seen claims that they want to get up to 900 km/h eventually but I take that with a pinch of salt. The planned top speed for commercial service beginning in 2027 is 500km/h to start with.
"a train can be much longer and thinner, so more energy efficient so long as displacement drag dominates skin drag."
The faster you go, the more skin drag becomes a major issue and at some point around 150km/h it becomes the dominant friction factor. That's why Elon wants to run his trains in partially evacuated tubes.
I'd suggest shark-tooth coatings but these trains need to run bidirectionally.
The Register 
Biting the hand that feeds IT
Copyright. All rights reserved © 1998–2025
