Levitation magnetic: description, features and examples

As you know, the Earth, by virtue of the existing world order, there is a certain gravitational field, and man's dream has always been to overcome it by any means. The magnetic levitation is a term rather fantastic than relating to everyday reality.

Initially, it meant a hypothetical ability to overcome in an unknown way an earthly attraction and move people or objects through the air without ancillary equipment. However, now the concept of "magnetic levitation" is already quite scientific.

Several innovative ideas are being developed at once, based on this phenomenon. And all of them in the future promise great opportunities for versatile application. True, the magnetic levitation will not be performed by magic methods, but using quite concrete achievements of physics, namely, the section studying magnetic fields and everything connected with them.

Very little theory

Among people far from science, there is an opinion that magnetic levitation is a guided flight of a magnet. In practice, this term means overcoming the object of gravity with the help of a magnetic field. One of its characteristics is magnetic pressure, it is used to "fight" with the earth's gravity.

Simply put, when gravity pulls the object down, the magnetic pressure is directed in such a way that it pushes it in the opposite direction - upwards. Thus, a levitation of a magnet occurs. The difficulty in realizing the theory is that the static field is unstable and does not focus at a given point, so it can not be effective to withstand attraction. Therefore, auxiliary elements are required, which will give the magnetic field dynamic stability, so that the levitation of the magnet was a regular phenomenon. As stabilizers for him, different techniques are used. Most often - an electric current through superconductors, but there are other developments in this area.

Technical levitation

Actually, the magnetic variety refers to a more extensive term for overcoming gravitational attraction. So, technical levitation: a review of methods (very brief).

With magnetic technology, we seem to have sorted out a little, but there is still an electric method. Unlike the first, the second can be used to manipulate products from a variety of materials (in the first case - only magnetized), even dielectrics. Electrostatic and electrodynamic levitation is also divided.

The possibility of particles under the influence of light to carry out the motion was anticipated by Kepler. And the existence of the pressure of light was proved by Lebedev. Movement of the particle in the direction of the light source (optical levitation) is called positive photophoresis, and in the opposite direction - negative.

Levitation aerodynamic, differing from the optical one is quite widely applicable in the technologies of the day of the present. By the way, the "pillow" is one of its varieties. The simplest air cushion is very easy to obtain - a lot of holes are drilled in the carrier substrate and compressed air is blown through them. In this case, the air lift balances the mass of the object, and it hovers in the air.

The last method known to science at the moment is levitation using acoustic waves.

What are the examples of magnetic levitation?

The fantasy dreamed of portable devices the size of a backpack, which could "levitate" a person in the right direction with a significant speed. Science has so far taken a different path, more practical and feasible - a train was created, moving with the help of magnetic levitation.

History of super-trains

For the first time, the idea of a composition using a linear engine was filed (and even patented) by the German engineer-inventor Alfred Zane. And it was in 1902. After this development of the electromagnetic suspension and a train equipped with it, appeared with an enviable regularity: in 1906 Franklin Scott Smith proposed another prototype, between 1937 and 1941. A number of patents on the same subject was received by Hermann Kemper, and a little later the British Eric Lazweit created a working prototype of a full-size engine. In the 60's, he also participated in the development of Tracked Hovercraft, which was to become the fastest train, but did not, because the lack of funding in 1973, the project was closed.

Only six years later, again in Germany, a magnetic cushion train was built, which was licensed for passenger transportation. The test track laid in Hamburg had a length of less than a kilometer, but the idea itself inspired the society so much that the train operated even after the exhibition closed, having managed to transport 50 thousand people in three months. Its speed, according to modern standards, was not so great - only 75 km / h.

Not an exhibition, but a commercial maglev (as the train using a magnet was called), shuttled between Birmingham Airport and the railway station from 1984, and held on for 11 years. The length of the path was even smaller, only 600 m, and over the canvas the train was raised by 1.5 cm.

Japanese version

In the future, the excitement about trains on a magnetic cushion in Europe subsided. But by the end of the 90th they were actively interested in such a country of high technologies as Japan. There are already quite a few long routes on its territory, over which maglevs fly using a phenomenon such as magnetic levitation. This country also owns high-speed records, set by these trains. The last of them showed a speed limit of more than 550 km / h.

Further prospects of use

On the one hand, the Maglevs are attractive for their rapid movement: according to the calculations of theorists, they can be dispersed in the near future up to 1,000 kilometers per hour. After all, they are activated by magnetic levitation, and only air resistance slows down. Therefore, making the maximum aerodynamic outlines of the composition greatly reduces its effect. In addition, due to the fact that they do not touch the rails, the wear of such trains is extremely slow, which is economically very profitable.

Another plus - reducing the noise effect: magnets move almost silently compared to conventional trains. The bonus is also the use of electricity in them, which helps to reduce the harmful impact on nature and the atmosphere. In addition, the train on a magnetic cushion is able to overcome steeper slopes, and this eliminates the need to lay a railroad track bypassing the hills and descents.

Application in power engineering

An equally interesting practical direction can be considered the wide application of magnetic bearings in key parts of mechanisms. Their installation solves the serious problem of wear of the raw material.

As you know, classical bearings wear off quite quickly - they constantly experience high mechanical loads. In some areas, the need to replace these parts means not only additional costs, but also a high risk for the people who service the mechanism. Magnetic bearings keep working capacity many times longer, so that their application is very suitable for any extreme conditions. In particular, in nuclear power engineering, wind technologies or industries, accompanied by extremely low / high temperatures.

Aircrafts

In the problem of how to implement magnetic levitation, the reasonable question arises: when, finally, will a full-fledged aircraft be manufactured and presented to progressive humanity, in which levitation will be used magnetic? After all, there are indirect evidence that such "UFOs" existed. Take, for example, the Indian "vimans" of the most ancient era, or the Hitler "disco", which is already closer to us in a temporal ratio, using, among other things, electromagnetic methods of organizing the lifting force. Preserved drawings and even photos of existing models are preserved. The question remains open: how to translate all these ideas into reality? But beyond the not too viable prototypes, modern inventors have not yet begun to work. Maybe it's too secret information?