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Old April 23rd, 2015, 03:43 PM   #901
SamuraiBlue
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Originally Posted by M-NL View Post
Downside of this rail design is that while Transrapid basically is a clamp around the rail, there is nothing in the Japanese system to prevent flight. If a similar accident as happened with Transrapid (collision with a maintenance vehicle) were to occur, there is nothing to stop the train from lifting off and leaving the tracks. Who knows where it will end up if that were to happen.
There is an invisible rope called magnetism that ties down the trainset from flying anywhere.
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Old April 23rd, 2015, 04:28 PM   #902
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Originally Posted by M-NL View Post
The interesting thing is that compared to the Transrapid switches are a lot easier: Basically a movable wall will do, instead of the entire track for Transrapid.

Downside of this rail design is that while Transrapid basically is a clamp around the rail, there is nothing in the Japanese system to prevent flight. If a similar accident as happened with Transrapid (collision with a maintenance vehicle) were to occur, there is nothing to stop the train from lifting off and leaving the tracks. Who knows where it will end up if that were to happen.
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There is an invisible rope called magnetism that ties down the trainset from flying anywhere.
******* magnets how do they work??


First, while the magnets on the Maglev do indeed support the train they only do so at high speeds. When the train is accelerating it is on rubber wheel up to like 150kph. As well, the magnets are kept in equilibrium between attraction and repulsion with the upper most magnets being in opposite polarity.

Second, for proper flight one needs to have a lifting body. Trains do not (unfortunately!) have lifting bodies. Even among aircraft it is fairly rare and limited to experimental models. The flight generated by commercial planes are due to the wings and not the fuselage.

In an accident though, it could possibly shoot upwards but that would be due to momentum alone. For the record though, at maximum speed 7 cars at an est. 40 tons each would be 3.9 GJ or roughly equivalent to one ton of TNT.
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Old April 23rd, 2015, 05:05 PM   #903
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Second, for proper flight one needs to have a lifting body. Trains do not (unfortunately!) have lifting bodies. Even among aircraft it is fairly rare and limited to experimental models. The flight generated by commercial planes are due to the wings and not the fuselage.

In an accident though, it could possibly shoot upwards but that would be due to momentum alone. For the record though, at maximum speed 7 cars at an est. 40 tons each would be 3.9 GJ or roughly equivalent to one ton of TNT.
No one is talking about proper flight, but when air gets under something, it might cause it to shoot upwards.

Try putting a mattress on the top of your car and holding it with just your hand. The moment the wind catches it on the highway, it will "fly" away.
Or look at certain boats, which are generally aerodynamically designed to NOT fly up from out of the water, yet do once the air gets underneath it:
https://www.youtube.com/watch?v=Zm9ZuXa2Z_I


So: will it be possible for an object on that track to lift the maglev up enough for the air to get a hold of it? No idea. I don't think that question has been answered here, yet.
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Old April 23rd, 2015, 09:08 PM   #904
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There is an invisible rope called magnetism that ties down the trainset from flying anywhere.
However when you take a look at magnetism formulas you will see that there is an inverse relation between force and distance. In simple terms: the more you separate the magnets out of their usual alignment the less force they exert. In this case we are talking electromagnets, so you have the possibility to increase or decrease forces when needed.
Still, an undetected boulder falling from a mountain could be enough.
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Old April 23rd, 2015, 10:09 PM   #905
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JAPAN | Maglev

Most of the line is tunneled. It is already mostly “roof-fenced”.

Last edited by bluemeansgo; April 25th, 2015 at 04:20 AM.
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Old April 24th, 2015, 04:04 PM   #906
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No one is talking about proper flight, but when air gets under something, it might cause it to shoot upwards.

Try putting a mattress on the top of your car and holding it with just your hand. The moment the wind catches it on the highway, it will "fly" away.
Or look at certain boats, which are generally aerodynamically designed to NOT fly up from out of the water, yet do once the air gets underneath it:
https://www.youtube.com/watch?v=Zm9ZuXa2Z_I


So: will it be possible for an object on that track to lift the maglev up enough for the air to get a hold of it? No idea. I don't think that question has been answered here, yet.
Well in my last paragraph, I do say that in an accident it could shoot off but it would be solely due to its momentum. A head-on collision would probably see it slice through whatever it is, you would need a fairly decent sized wedge to be able to angle the train quick enough before it slows down since the induction only works at high-speeds. I would hazard a guess that the nature of the magnetic induction would actually limit such accidents because deviations in direction and speed would actually slow the train down.

A bit off tangent though, maglevs can be used as a form of non-rocket propulsion or a hybrid system with respect to aerospace vehicles. Imagine a long track that gently curves upwards, if the track is long enough the final velocity would be greater than escape velocity and the vehicle could continue without engines. I believe its called a Star Tram.
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Old April 24th, 2015, 05:23 PM   #907
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I believe its called a Star Tram.
Probably more widely known as "Mass driver"
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Old April 25th, 2015, 04:47 AM   #908
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I'm sure it is something the engineers have thought about. That being said Japanese train systems are designed to avoid such situations instead of to cope with them.

The boat analogy is flawed as well. Boats are specifically designed to life out of the water. The maglev is specifically designed to stay down on the track just like f1 cars are aerodynamically designed to push down. If the train was lifted it would still have to overcome the forces of air pressure pushing it down.
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Old April 26th, 2015, 09:09 AM   #909
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What fence will stop a 500 km/h flying train?
bacially it does not fly and get line out



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Old April 26th, 2015, 03:54 PM   #910
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Those videos are super cool ( literally ). Thanks for sharing
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Old April 26th, 2015, 06:24 PM   #911
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Originally Posted by castermaild55 View Post
bacially it does not fly and get line out



Those videos show quantum locking technology.


The JR Maglev uses Electrodynamic suspension, and does use a guidance system.
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Old May 14th, 2015, 09:02 AM   #912
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Those videos show quantum locking technology.


The JR Maglev uses Electrodynamic suspension, and does use a guidance system.
yes it does


however it is same..
this guidance is used when speed is slow because it must stop at station

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Last edited by castermaild55; May 14th, 2015 at 11:27 AM.
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Old May 14th, 2015, 04:27 PM   #913
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I don't read Chinese. I can't find any sources saying the TransRapid maglev or JR maglev uses quantum locking technology. JR Maglev uses electrodynamic suspension, not quantum locking.
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Old May 14th, 2015, 05:27 PM   #914
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I don't read Chinese. I can't find any sources saying the TransRapid maglev or JR maglev uses quantum locking technology. JR Maglev uses electrodynamic suspension, not quantum locking.
It's all in Japanese and although I don't understand what you mean by quantum locking but all superconductive material within a magnetic field shows the same phenomenon shown within the vid.
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Old May 14th, 2015, 06:05 PM   #915
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It's all in Japanese and although I don't understand what you mean by quantum locking but all superconductive material within a magnetic field shows the same phenomenon shown within the vid.
My apologies, I was watching the picture on a very small screen so I could not see what script it was exactly.


Anyway, quantum locking, which was shown in the videos you posted, is a very special phenomenon, and as far as I know it is not the way current Japanese Maglev technology works.

I like to learn, so if you can find sources showing Japanese Maglev does use quantum locking in stead of electrodynamic suspension, I would love to see them.
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Old May 14th, 2015, 06:40 PM   #916
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I will say it again a superconductive material suspended within a magnetic field will result in the same phenomenon as shown within the vid.
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Old May 15th, 2015, 04:13 AM   #917
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No, that train is not locked into place due to quantum locking, which is the phenomenon shown in the vid.

Seriously, read up on quantum locking. It is totally different from what the JR Maglev does.
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Old May 15th, 2015, 05:29 AM   #918
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No, that train is not locked into place due to quantum locking, which is the phenomenon shown in the vid.

Seriously, read up on quantum locking. It is totally different from what the JR Maglev does.
http://physics.about.com/od/quantump...Levitation.htm
Quote:
The Meissner effect dictates that a superconductor in a magnetic field will always expel the magnetic field inside of it, and thus bend the magnetic field around it.
Since the superconductive material is situated on the sides of the train the Meissner effect locks the train into the middle of the tracks.
Also note that the magnetic field is on a constant flux being generated by a AC elctro-magnetic coils on the sides of the guide way so the Meissner effect is also fluctuating making the train move forwards. The secondary coils provides lift through electric induction by the superconductive magnetic field which again creates a Meissner effect this time providing lift due to the coils position relative to the superconductive coil's position on the sides of the train.
Basically Quantum locking can be turned on and/or off if you can turn on and/or off the magnetic field which can be done easily through elector-magnets.
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Old May 15th, 2015, 06:59 AM   #919
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Selective quoting. The videos posted show not only the Meissner effect, but also flux pinning, or quantum locking. That is something the JR Maglev just does not do, or at least not in the way shown in those videos. Otherwise it could have the cool tracks as shown in the videos, and go through bends and loops without any guide rails on the side. It can not do this.

It is guided and levitated from the sides. It is not levitated from the bottom and kept in place through quantum locking.




A small recap how we got to this point to show the ridiculousness of it all:
1. someone questioned what would happen if the train, for some reason (for example, collision with a maintenance vehicle on the track), would be propelled upwards and out of the tracks
2. someone said that could be remedied by putting a "fence" as a roof to stop it from flying off the tracks
3. I laughed questioning what kind of fence could stop a 500 km/h train
4. Someone responded with some cool, though irrelevant, videos showing a completely different phenomenon of quantum locking to prove that a JR Maglev could never be propelled from its tracks, completely missing the point that JR Maglev does not use quantum locking in such a way, and even if it did, it could still be dislodged from its tracks and propelled out of them by a collision with a maintenance vehicle on the track.




So now, I will try to get back on topic and hope some JR Maglev enthusiasts are present to finally answer the question: what measures have JR taken to prevent a foreign object from getting on the tracks that could propel the maglev out of the tracks?
They must have planned ahead for such a thing, so what did they do to limit the risk?
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Old May 15th, 2015, 02:24 PM   #920
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Originally Posted by Silly_Walks View Post


Selective quoting. The videos posted show not only the Meissner effect, but also flux pinning, or quantum locking. That is something the JR Maglev just does not do, or at least not in the way shown in those videos. Otherwise it could have the cool tracks as shown in the videos, and go through bends and loops without any guide rails on the side. It can not do this.
Go back and educate yourself.

All three you talk about is one and the same. The phenomenon is based on the Meissner effect which repels magnetic field and thus bend the magnetic field around it.
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