As you know, due to the prevailing world order, the Earth has a certain gravitational field, and a person’s dream has always been to overcome it by any means. Magnetic levitation is a fantastic term rather than everyday reality.
Initially, it was understood as a hypothetical ability to overcome gravity in an unknown way and to move people or objects through the air without auxiliary equipment. However, now the concept of "magnetic levitation" is already quite scientific.
Several innovative ideas are being developed at once, which are based on this phenomenon. And all of them in the future promise great opportunities for versatile use. True, magnetic levitation will not be carried out by magic, but using the very specific achievements of physics, namely the section studying magnetic fields and everything connected with them.
Quite a bit of theory
Among people far from science, there is an opinion that magnetic levitation is a guided flight of a magnet. In fact, this term means overcoming the subject of gravity using a magnetic field. One of its characteristics is magnetic pressure, and it is used to “fight” against gravity.
Simply put, when gravity pulls an object down, the magnetic pressure is directed so that it pushes it in the opposite direction - up. So there is a levitation of a magnet. The difficulty in implementing the theory is that the static field is unstable and does not focus at a given point, so it may not fully resist attraction. Therefore, auxiliary elements are required that will give the magnetic field dynamic stability so that the levitation of the magnet is a regular phenomenon. As stabilizers for it, various 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 the broader term of overcoming gravitational attraction. So, technical levitation: a review of methods (very brief).
We seem to have sorted out a bit with magnetic technology, but there is still an electrical 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 are also separated.
The possibility of particles under the influence of light to carry out motion was predicted by Kepler. And the existence of light pressure is proved by Lebedev. The movement of a particle in the direction of the light source (optical levitation) is called positive photophoresis, and in the opposite direction, negative.
Aerodynamic levitation, differing from optical, is quite widely applicable in the technologies of the present day. By the way, the “pillow” is one of its varieties. The simplest air cushion is very easy to obtain - many holes are drilled in the carrier substrate and compressed air is blown through them. In this case, the air lifting force balances the mass of the object, and it soars in the air.
The last method known to science at the moment is levitation using acoustic waves.
What are some examples of magnetic levitation?
Science fiction dreamed of portable devices the size of a backpack that could “levitate” a person in the direction he needed with considerable speed. So far, science has taken a different path, more practical and feasible - a train was created that moves using magnetic levitation.
Super Train History
For the first time, the idea of a composition using a linear motor was submitted (and even patented) by the German inventor Alfred Zane. And that was in 1902. After this, the development of the electromagnetic suspension and the train equipped with it appeared with enviable regularity: in 1906, Franklin Scott Smith proposed another prototype, between 1937 and 1941. Herman Kemper received a number of patents on the same subject, and a bit later, Briton Eric Laiswaite created a working life-size engine prototype. In the 60s, he also participated in the development of Tracked Hovercraft, which was supposed to be the fastest train, but did not, because the project was closed in 1973 due to insufficient funding.
Only six years later, and again in Germany, a magnetic cushion train was built, which received a passenger license. The test track, laid in Hamburg, was less than a kilometer long, but the idea inspired the society so much that the train also functioned after the exhibition closed, having managed to transport 50 thousand people in three months. Its speed, by modern standards, was not so great - only 75 km / h.
Not an exhibition, but a commercial Muggle (as the train using a magnet was called), it ran between Birmingham Airport and the railway station since 1984, and held out for 11 years. The path was even shorter, only 600 m, and the train rose 1.5 cm above the train.
Japanese version
In the future, the excitement about magnetic cushion trains in Europe has subsided. But by the end of the 90s, such a high-tech country as Japan was actively interested in them. On its territory several rather long routes have already been laid along which the Maglev fly, using such a phenomenon as magnetic levitation. The same 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 use prospects
On the one hand, Muggle people are attractive for their fast moving capabilities: according to the calculations of theorists, they can be dispersed up to 1, 000 kilometers per hour in the near future. After all, they are driven by magnetic levitation, and only air resistance slows down. Therefore, giving the maximum aerodynamic outline to the composition greatly reduces its effect. Moreover, due to the fact that they do not touch the rails, the wear and tear of such trains is extremely slow, which is economically very profitable.
Another plus is the reduction in sound effect: Muggles move almost silently compared to conventional trains. A bonus is also the use of electricity in them, which reduces the harmful effects on nature and the atmosphere. In addition, the magnetic cushion train is capable of overcoming steeper slopes, and this eliminates the need to lay railway tracks bypassing hills and descents.
Energy Applications
No less interesting practical direction can be considered the widespread use of magnetic bearings in key components of mechanisms. Their installation solves the serious problem of wear of the source material.
As you know, classic 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 people who service the mechanism. Magnetic bearings remain operational many times longer, so their use is very advisable for any extreme conditions. In particular, in nuclear energy, wind technology or industries, accompanied by extremely low / high temperatures.
