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The One
5th August 2014, 13:26
http://asia.nikkei.com/var/site_cache/storage/images/node_43/node_51/2014/201407/20140723/20140723_l0_linear/1183410-1-eng-GB/20140723_L0_Linear_article_main_image.jpg
A maglev train runs along a test track in Yamanashi Prefecture, west of Tokyo. © Courtesy of JR Tokai


TOKYO -- JR Tokai, a railway operator in central Japan, is scheduled to begin construction this autumn on the Linear Chuo Shinkansen line. The line's magnetically levitated, or maglev, trains will be the fastest in the world, running at up to 500kph.

The train reaches speeds more common to airplanes by using a superconducting maglev system that propels it forward on a magnetic field between the track and the carriage, eliminating friction. The secret is Japan's superconductivity technology, which has improved over many years. The new line is scheduled to go into service between Tokyo and Nagoya in 2027, cutting travel time between the two cities by more than half, from 90 minutes on today's shinkansen bullet trains to 40 minutes.

http://asia.nikkei.com/var/site_cache/storage/images/node_43/node_51/2014/201407/20140725/20140724maglevw/1192615-1-eng-GB/20140724maglevW.png

JR Tokai is testing the maglev train on a stretch of track that runs for about 43km in Yamanashi Prefecture. It floats about 10cm above the track, thanks to a series of superconducting magnets integrated into the 3-meter-wide cars, including the couplings. At a speed of 500kph, the train runs from one end of the test track to the other -- about the distance of a marathon -- in just 5 minutes.

Pole position

The maglev train runs along a "track" called a guideway, which has a U-shaped cross-section. Propulsion coils run in elliptical loops along both walls of the guideway, generating magnetic force when electricity runs through them. Levitation and guidance coils, meanwhile, are formed into figure eights that create their own magnetic force when the train's superconducting magnets pass over them. These coils are arranged in cases measuring about 1 meter square along the guideway.

When an electric current flows through the propulsion coils, a magnetic field is produced. The forces of attraction and repulsion between the coils and the superconducting magnets on the train propel the car forward. The train's speed is adjusted by altering the timing of the polarity shift in the propulsion coils' magnetic field between north and south. The train has a maximum recorded speed of 581kph, although it is technically possible to raise that figure much higher.

To create levitation and lateral balance in the train, a phenomenon called electromagnetic induction is used. As the train passes along the guideway, an electric current is induced in the levitation and guidance coils, creating opposite magnetic poles in the upper and lower loops of the figure eights. The upper loops become the polar opposite of the train's magnets, producing attraction, which pulls the train up. The lower loops have the same pole as the magnets. This generates repulsion, which pushes the train in the same direction -- up. The two forces combine to levitate the train, while maintaining its lateral balance between the walls of the guideway.

Slip-sliding away

The front and rear cars weigh 35 tons each, and the cars in between weigh 25 tons each. Despite the heavy load, the superconducting magnets produce a force of about 1 tesla, strong enough to push the train about 10cm above the track. In theory, the guideway requires no bottom, since the levitating force is created by the coils on the walls.

Superconducting magnets generate force in the same way as ordinary electromagnets, but they are smaller and lighter for an equivalent amount of force. Because they have no electrical resistance, a current passing through them continues to flow, and can be converted fully into a strong magnetic force. For ordinary magnets to produce the same amount of force, more electric current has to be applied, which makes them 100 times as heavy as superconducting magnets, said Ken Nagashima, chief of the maglev systems technology division at the Railway Technical Research Institute. This makes them impractical for use in maglev trains.

A niobium-titanium alloy has been used to create superconducting magnets for maglev trains since they were first developed in 1962. But to reach superconductivity, they must be kept cold. Very cold. The alloy is cooled with liquid helium to a temperature of minus 269 C. Although the alloy retains superconductivity at temperatures up to minus 263 C, the maglev system operates at 6 degrees lower to produce sufficient magnetic force.

Critical thinking

Superconductivity was discovered in mercury at a temperature of minus 269 C by Heike Kamerlingh Onnes, a physicist at Leiden University in the Netherlands, more than 100 years ago.

As scientists developed new materials, the temperature at which superconductivity occurs, known as the critical temperature, rose gradually. The niobium-titanium alloy developed in the 1950s was easy to process and suited to industrial use. Before the maglev train system was developed, magnetic resonance imaging devices using niobium-titanium alloys were developed in the U.S. and the U.K. in the latter half of the 1970s. MRI machines are now commonplace at hospitals. But because liquid helium is expensive, industrial applications for superconductivity have not spread widely beyond MRI machines and maglev trains.

In 1986, a Swiss research team discovered a copper oxide that has superconductivity at a relatively high temperature in a way that could not be explained by conventional theory. Although the critical temperature is still chilly, at minus 243 C, the phenomenon was dubbed high-temperature superconductivity because it exceeded the limit of the theory. Copper oxides that become superconductive when cooled with liquid nitrogen (minus 196 C) were discovered in the U.S. in 1987 and in Japan in 1988. These are called the yttrium type and the bismuth type, respectively, based on their chemical composition. They are potentially valuable because liquid nitrogen is cheaper than liquid helium.

JR Tokai ran tests for a maglev train equipped with bismuth-type high-temperature superconducting magnets in 2005 with a view to using them in trains in the future. The company found that the train was able to maintain a maximum speed of about 554kph using superconducting magnets cooled to minus 253 C, 16 degrees higher those cooled with liquid helium. In addition, the magnets can be cooled directly by refrigerators without the use of either liquid helium or liquid nitrogen.

Such refrigerators have a simple structure and are easier to maintain than those using liquid coolants. Based on the results of the test runs, JR Tokai is developing a high-temperature superconducting magnet.

The holy grail for superconductivity is to produce the phenomenon at room temperature. So far, the highest critical temperature is minus 138 C. If a superconducting material can be commercialized that functions at room temperature, power losses in electrical equipment would be reduced and fewer power plants would be needed, resulting in far less carbon dioxide being pumped into the atmosphere and a lower risk of global warming


https://www.youtube.com/watch?v=8FdJhBzTTx4

http://asia.nikkei.com/magazine/20140731-Enter-Alibaba/Tech-Science/Look-Ma-no-wheels!-How-maglev-trains-reach-500kph

norman
5th August 2014, 13:39
A super-collider loaded with a capsule full of humans, great !

The One
5th August 2014, 13:43
I think the technology is awesome.Imagine what else they could achieve

norman
5th August 2014, 14:17
I think the technology is awesome.Imagine what else they could achieve

yep, it's amazing. Still couldn't build the pyramids though :)

The One
5th August 2014, 15:27
yep, it's amazing. Still couldn't build the pyramids though :)


Agreed maybe the suppression of technology is slowly getting out.

ronin
5th August 2014, 15:40
i read a few year back that there where two forms of maglev(magnetic transportation) that where available but we where only allowed to focus on one!
i think they have had this tech a few years,ever here of the high speed trains under places like the whitehouse,dulce maybe london ect.
what usually happens when the public are given the latest technology is that they have secured a higher technology,so it is safe to release the last one.

magnetic propulsion could help with the reduction of up to 80 per cent of your fuel bills in the home and transport.
is this why we are seeing the high rise of fuel bills from electricity,gas ect because they know when this tech gets out it could make them redundant?
as for spaceflight well........

jimmer
5th August 2014, 15:57
what could possibly go wrong?

Stoat muldoon
5th August 2014, 17:38
This is really old technology don't you think ?

History
First patent

High-speed transportation patents were granted to various inventors throughout the world.[7] Early United States patents for a linear motor propelled train were awarded to the German inventor Alfred Zehden. The inventor was awarded U.S. Patent 782,312 (14 February 1905) and U.S. Patent RE12,700 (21 August 1907).[8] In 1907, another early electromagnetic transportation system was developed by F. S. Smith.[9] A series of German patents for magnetic levitation trains propelled by linear motors were awarded to Hermann Kemper between 1937 and 1941.[10] An early modern type of maglev train was described in U.S. Patent 3,158,765, Magnetic system of transportation, by G. R. Polgreen (25 August 1959). The first use of "maglev" in a United States patent was in "Magnetic levitation guidance system"[11] by Canadian Patents and Development Limited.

So where's the good stuff hiding :eyebrows:

ronin
5th August 2014, 17:41
the good stuff is.

look up.

The One
5th August 2014, 17:42
So where's the good stuff hiding

Great point mate.This stuff is years old and just think what they can do with it.Like everything its been suppressed from the masses and the greedy nations of the world keep everything to themselves.

The are drilling the earth to death and just think that the simplest of things could probably solve all our problems

Stoat muldoon
5th August 2014, 18:20
Great point mate.This stuff is years old and just think what they can do with it.Like everything its been suppressed from the masses and the greedy nations of the world keep everything to themselves.

The are drilling the earth to death and just think that the simplest of things could probably solve all our problemsNo profit in that in solving that problem .

mojo
6th August 2014, 17:48
there shouldnt be a surprise to a few that these trains are already in use underground. Keep thinking about economies of scale and how the tech trickles into the public sector...

ronin
6th August 2014, 21:32
it,s like the stealth bomber,it was operational i think about ten years before it was discovered or the public where informed about it.
it is said that technology is fifty or a hundred years ahead of what we know now.
since the 40,s it has grown at a massive rate,wonder why that is?
only problem is those who are in the r and d of new tech are private companies and the military.

imagine what we could achieve if we used the tech for humanity and the planet.
instead of the greed that we see now.

norman
6th August 2014, 21:45
....imagine what we could achieve if we used the tech for humanity and the planet.
instead of the greed that we see now.....



I CAN !

But, I can also imagine a turbo charged dysfunctional society, and that scares me.

ronin
6th August 2014, 21:56
are we not now dysfunctional,just look at our believes,the system and our personal goals.
now imagine a world when everyone is striving for the same goal.
you choose what area you want to work in.
agriculture,natural medicine,schooling,true history,spaceflight,spiritualism.
a functional society where there is no greedy companies and no ruling elite.

norman
6th August 2014, 22:16
If apple or microsoft or Google put anti gravity personal vehicles on the market this year, can you imagine the chaos that would result within a few months or at most a couple of years.

95% of the population are absolutely NOT READY for that much freedom and energy availability.

norman
7th August 2014, 18:58
are we not now dysfunctional,



My point exactly. Now imagine introducing fancy technology and 'free' energy into that.

It boggles my mind.

ronin
7th August 2014, 19:12
My point exactly. Now imagine introducing fancy technology and 'free' energy into that.

It boggles my mind.

and just is to judge when we are ready for new technology?
you maybe surprised at how quickly we do become acceptable of the new!
even though we and i mean our age group may find new technology hard to fathom ,it is fact that our children are adapting to it very quickly.

just as we(our age group) fumble around trying to figure out how to work a i pad.
a three year old already can navigate it.

i don,t think anyone would be upset but be welcome the tech in their lives as a means to empower themselves.

norman
7th August 2014, 19:27
and just is to judge when we are ready for new technology?
you maybe surprised at how quickly we do become acceptable of the new!
even though we and i mean our age group may find new technology hard to fathom ,it is fact that our children are adapting to it very quickly.

just as we(our age group) fumble around trying to figure out how to work a i pad.
a three year old already can navigate it.

i don,t think anyone would be upset but be welcome the tech in their lives as a means to empower themselves.

Empowered dysfunctionality is my idea of hell getting hotter.

I still say most people, and that includes babies being born today, are not ready for it. There has to be a shift first.

ronin
7th August 2014, 19:33
depends if you are looking at it from a commercial or personal use.
maglev trains for ten years then bring in maglev cars.......