. Energy sources usually adopt devices that can store 10 ~ 100 MJ energy. At present, the energy sources used in the experiment are storage batteries, magnetic flux compression devices and unipolar generators, among which unipolar generators are the most promising energy sources in the near future. Accelerator is a device that converts electromagnetic energy into kinetic energy of shells and makes them reach high speed. There are two main categories: rail gun accelerator powered by low-voltage DC monopole generator and coaxial synchrotron with discrete or continuous coil structure. A switch is a device that connects an energy source and an accelerator, and it can introduce a million amperes of current into the accelerator in a few milliseconds. One of them consists of two copper rails and a slider that can slide in them. As early as19th century, scientists found that the charge and current in the magnetic field would be influenced by Lorentz force. At the beginning of the 20th century, some people put forward the idea of using Lorentz force to launch shells. During the two world wars, France, Germany and Japan were all studying electromagnetic guns. After World War II, other countries also conducted research in this field. Since the early 1970s, the technology related to electromagnetic emission has made great progress. The Australian National University built the first electromagnetic transmitter, which accelerated the plastic block (shell) weighing 3 grams to the speed of 6000 meters per second. Since then, Australian and American scientists have made different types of experimental prototypes and conducted many launch experiments. The electromagnetic gun powered by a unipolar generator has been able to accelerate the 365,438+08g projectile to the speed of 4,200m/s. The magnetic flux compression electromagnetic gun has been able to accelerate the 2g projectile to the speed of11000m/s..
Principles for editing this paragraph
fundamental principle
The principle of electromagnetic gun is very simple. /kloc-in the 9th century, the British scientist Faraday discovered that the wires in the magnetic field were passing through the schematic diagram of the electromagnetic gun.
Electricity will be pushed by a force, and at the same time, if the conductor cuts the magnetic field lines in the magnetic field, current will also be generated on the conductor. This is the famous Faraday's law of electromagnetic induction. It is according to this law that people invented the generators and motors that are widely used now, which is also the basic principle of electromagnetic guns. In other words, the electromagnetic gun is just a special kind of motor, because its rotor is not rotating, but a shell with linear acceleration. So how to generate a magnetic field to drive the shell, let the current pass through the shell, and make it get forward power? One of the simplest electromagnetic guns is designed as follows: a track consists of two conductors with a shell in the middle, so that current can establish a loop through the three conductors. Put this device in a magnetic field, energize the shell, and the shell will accelerate forward. 1980 The experimental electromagnetic gun built by Westinghouse for Star Wars is basically such a structure. It accelerates the shell with a mass of 300 grams to about 4 kilometers per second. If it is in a vacuum, this speed can be increased to 8~ 10 km per second, which has exceeded the speed of the first universe and has the theoretical qualification as a new space launcher.
technical matters
To turn this theoretical possibility into reality, the following problems need to be solved: First, the acceleration of the experimental electromagnetic gun is too large for people to bear. There is only one way to solve this problem, and that is to extend the acceleration time. However, this must be at the expense of adopting a longer orbit. Because the human body can only bear the long-term acceleration of about 3 times the gravity acceleration, the orbital length of the electromagnetic gun that meets the human body's bearing capacity (after calculation, it takes about 1000 km to reach the first cosmic speed! ) it is technically difficult to achieve. Second, if the electromagnetic gun is installed horizontally on the ground, the shells flying from the muzzle will still slow down quickly under atmospheric resistance, and it is difficult to fly smoothly around the earth. Therefore, the electromagnetic gun used for space launch must have its outlet at the top of the mountain with thin air. Third, at present, the quality of the shells that can be fired by electromagnetic guns is not large, which is caused by insufficient acceleration ability. The force to accelerate the projectile is proportional to the product of magnetic field and current. Superconducting magnets are generally used to obtain a sufficiently strong accelerating magnetic field. It is a mature technology to generate magnetic field with superconducting coil, but superconducting magnet needs to be cooled to a very low temperature (such as liquid helium temperature, about -269℃) to play its role, which is a problem for military applications, because it will greatly reduce the flexibility of launching device. However, as a fixed space launch device, these can be basically ignored. If high-temperature superconducting strong magnets can be successfully developed, the requirements for low-temperature conditions can be relaxed. Principle of electromagnetic gun
The fourth technical problem about the electromagnetic gun is related to the third one, because if the magnetic field is not strong enough, the only way to improve the acceleration ability is to let the projectile pass a large enough current. Therefore, there are troubles such as high current heating and gun body ablation. Fortunately, these troubles are not very important for space launch, because the length of electromagnetic gun as a weapon should be strictly limited, and as a launching tool, a gun body of several kilometers or even more than ten kilometers is not a problem, but only requires high accuracy in structure. In addition, extending the orbit can also reduce the acceleration borne by the projectile. After calculation, the projectile accelerates from standstill to the first cosmic speed in a 5-kilometer-long orbit, and the acceleration is 600 times that of gravity, which is smaller than that of ordinary mortars, but it is obviously unbearable, and it is almost impossible to build an acceleration orbit of 1000 km on the earth, so I gave up the idea of launching people with electromagnetic guns. Finally, some people think that it may be technically difficult to build an acceleration orbit with a kilometer length and a strong magnetic field, but this is just a guess that we don't know the existing technical level of mankind. In fact, most particle accelerators and colliders have several kilometers or even dozens of kilometers of acceleration and energy gathering rings. Moreover, they not only require extremely high accuracy in loop construction, but also need to set strong magnetic fields at various turning and control points. In other words, people have completely mastered the basic technology of making cosmic electromagnetic guns, but the fields they use are different. The real difficulty is that no one has ever put the super accelerator in the alpine mountain area, and the traffic conditions on the Qinghai-Tibet Plateau are not good at present. As for the launching cost of the electromagnetic gun, if we don't consider the low-temperature liquid cost that produces strong magnetic field, it is only electricity and non-recyclable shell, and the daily maintenance cost is about the same as that of a high-speed subway with the same length. At most, a short opening needs to be equipped with a full-time snow sweeper or a movable cover, and it will be solved.
Edit the characteristics of this paragraph
(1) The electromagnetic driving force is large and the projectile velocity is high. The pulse power of electromagnetic emission is about 10 times of the gun's launching force, so the projectile launched with it has a high speed. The firing rate of general artillery is about 0.8 km/s, and the firing rate of rifle bullets is 1 km/s. Electromagnetic guns can accelerate a 3-gram projectile to 1 1 km/s and a 300-gram projectile to 4 km/s. Some experts even predict that the future speed can reach/kloc-0.
Meter/second. Speed is particularly important for space-based anti-missile systems. Because the higher the speed of the column loader, not only the interception efficiency is high. But also can greatly reduce the number of space-based weapons. (2) The stability of the projectile is good. The thrust of the electromagnetic gun projectile in the barrel is electromagnetic force, which is very uniform, and the electromagnetic thrust is easy to control, so the stability of the projectile is good, which is conducive to improving the hit accuracy. (3) Good concealment. The electromagnetic gun does not produce flame, smoke or shock wave when it is launched, so it is hidden in the battle and is not easy to be found by the enemy. And it uses low-grade fuel as energy instead of traditional gunpowder. This is beneficial to the safety of the launching position. (4) Projectile emission energy is adjustable. The magnitude of electromagnetic force can be quickly adjusted according to the nature and nominal size of the target, thus controlling the launch energy of the projectile. (5) More economical. Compared with conventional weapons, the cost per joule of gun propellant is 10 USD, and that of electromagnetic gun is 0. 1 USD. Compared with other space weapons, electromagnetic guns are more economical.
Edit this paragraph classification
Korgon
Coilgun, also known as AC coaxial coilgun, is the earliest form of electromagnetic gun, which consists of accelerating coil and projectile coil. Its working principle is the magnetic field interaction between electrified coils. The accelerating coil is fixed in the barrel. When alternating current is applied, the alternating magnetic field will generate induced current in the projectile coil. The interaction between the magnetic field of induced current and the magnetic field of accelerating coil current produces a magnetic field force, which will accelerate the movement of the projectile and launch it.
Railgun
Rail guns use the ampere force of the interaction between rail currents to launch projectiles. It consists of two parallel long straight tracks, and a slider with a small mass is placed between the tracks as a projectile. When two tracks are connected to the power supply, a strong current flows in from one track, and when it flows back from the other track through the slider, a strong magnetic field will be generated between the two track planes. Under the action of ampere force, the projectile will be launched at a great speed. This is the launching principle of the rail gun.
Electric heating gun
The principle of electrothermal gun is completely different from the above two electromagnetic guns, and its structure has many forms. The simplest one is to use a general gun barrel, in which an electrode connected with a plasma burner is arranged, and the burner is installed at the tail of the gun. When a high voltage is applied between the two poles of the plasma burner, an arc will be generated, which will evaporate the plasma generating material (such as polyethylene) placed between the two poles. The evaporated material will become overheated high-pressure plasma, thus accelerating the projectile.
Reconnect the spray gun
The reconnection gun is a non-contact electromagnetic launcher with multi-stage acceleration. It has no barrel, but it requires the projectile to have a certain initial velocity before entering the reconnection gun. Its structure and working principle are that two rectangular coils are spaced up and down with a gap in the middle. The rectangular "shell" is subjected to strong magnetic field force in the magnetic field generated by two rectangular coils and accelerates through the gap. Reconnecting gun is the latest development form of electromagnetic gun.
Edit this paragraph to develop.
1845, Charles Wheatstone made the world's first reluctance DC motor, and used it to throw a metal rod into an electromagnetic gun to launch a spaceship.
Shooting 20 meters away. Since then, the German mathematician Kirby has put forward the idea of making "electric guns" by electromagnetic propulsion. Birkeland, a professor of physics at the University of Oslo, first formally put forward the concept of electromagnetic launch/electromagnetic gun and carried out experiments. He obtained the patent of electric gun at 190 1. 1920, France's "Fortune" Villepler published the article "Electric Gun". Almost at the same time, the electric gun company in Philadelphia, USA, developed an electromagnetic accelerator for artillery. During World War II, Germany and Japan developed electromagnetic guns under the stimulation of military demand. German hensley used electromagnetic gun to accelerate 10g projectile to initial velocity 1.2km/s ... But after World War II, there was less news about electromagnetic gun, and people seemed to pay more attention to magnetic levitation and high-temperature superconducting technology. The reason is probably that it cannot solve the problems of stability and miniaturization of instantaneous huge energy supply. In the 1970s, Dr. Richard Marshall of Australian National University used new technology to accelerate a 3-gram projectile to 5.9 km/s, which proved experimentally that it was feasible to propel an object to ultra-high speed by electromagnetic force. After his achievement 1978 was published, it attracted special attention from the military of various countries. The US National Defense Commission concluded that "future high-performance weapons must be based on electric energy". The U.S. Department of Defense has set up a "Joint Committee on Electromagnetic Guns" to coordinate the research work of electric guns dispersed by the Army, the Department of Energy, the National Defense Atomic Energy Agency and the Strategic Defense Initiative. 1992, the United States has pushed the electromagnetic gun sample gun with a caliber of 90 mm and muzzle kinetic energy of 9 MJ to Yuma shooting range for testing. From the laboratory to the shooting range, the electromagnetic gun shows that the miniaturization technology of power supply has made a breakthrough.
The purpose of editing this paragraph
As a developing high-tech weapon, electromagnetic gun has a wide range of military uses. (1) Used in space-based anti-missile system: Due to its extremely high initial velocity, electromagnetic guns can be used to destroy low-orbit satellites and missiles in space, and can also intercept missiles launched by ships and armor. Therefore, in the "Star Wars" plan of the United States, the railgun has become a major research task. (2) Used in air defense systems: The US military believes that electromagnetic guns can be used to perform air defense tasks instead of air defense weapons and air defense missiles. The United States is developing an electromagnetic gun with a length of 7.5 meters, a firing rate of 500 rounds per minute and a range of tens of kilometers, and is ready to replace the "Vulcan-phalanx air defense system" on board. It can not only attack all kinds of aircraft in the air, but also intercept air-to-ship missiles from a long distance. Britain is also actively developing anti-aircraft electromagnetic guns for armored vehicles. (3) For anti-armor weapons: American shooting tests prove that electromagnetic guns are an effective means to deal with tank armor. A projectile with a mass of 50g and a speed of 3km/s can penetrate armor with a thickness of 25.4mm. It is also reported that an electromagnetic gun is used in the test. It can completely penetrate the simulated armor thickness of T-72 and T-80 tanks. It can be seen that the electromagnetic gun has strong penetration ability and is an excellent anti-armor weapon. (4) Used for refitting conventional artillery: With the development of electromagnetic launching technology, the range of conventional artillery can be greatly improved by installing an electromagnetic acceleration system at its muzzle. The United States increased the range of artillery to 150km. By using this technology.
Edit the foreground of this paragraph.
Because of the above characteristics, the electromagnetic gun is regarded as a new weapon in the future by navies all over the world, and its application prospect is broad. 1. Electromagnetic gun can be used in space-based anti-missile system. Because of its extremely high initial velocity, electromagnetic guns can be used to destroy low-orbit satellites and missiles, and also to intercept missiles launched by warships. Due to the high initial velocity and high firing rate of electromagnetic gun, some American military experts believe that electromagnetic gun can be used to replace air defense weapons and missiles to perform air defense tasks. For example, the United States is developing an electromagnetic gun with a firing rate of 500 rounds per minute and a range of tens of kilometers, ready to replace the "dense array air defense system" on ships. It can not only attack all kinds of aircraft in the air, but also intercept air-to-ship missiles from a long distance. Britain, England
Air defense electromagnetic gun. 3. Used as an anti-tank weapon. Due to the high muzzle velocity, the electromagnetic gun has strong armor-piercing ability, which can effectively penetrate the tank armor and become an anti-tank weapon. The United States has conducted an electromagnetic gun shooting test: the electromagnetic gun can shoot a shell with a mass of 50g and a speed of 3km/s, and can penetrate the armor with a thickness of 25.4mm It is also reported that the electromagnetic gun can completely penetrate the armor thickness of T-72 and T-80 tanks. Therefore, the electromagnetic gun has strong penetration ability and is an excellent anti-tank weapon. With the development of electromagnetic launch technology, installing an electromagnetic acceleration system at the muzzle of a common gun can greatly improve the range of the gun, so that the electromagnetic gun is expected to be equipped with artillery units. The United States Marine Corps is also interested in electromagnetic guns. The US Marine Corps often carries out combat missions overseas, and it needs long-range rapid strike weapons such as electromagnetic guns to provide fire support for soldiers fighting along the coast. The US Army is also developing smaller electromagnetic guns for land warfare. 5. Used to equip naval vessels. Due to the characteristics of electromagnetic gun, it is expected to replace artillery and become a new type of naval gun equipped with naval vessels. The US Navy is going to equip American ships with electromagnetic guns. Some experts in the US military believe that the electromagnetic gun may become a new weapon for the future US Navy. Therefore, Admiral Roughead, former US Naval Operations Secretary, called it a revolution that would bring "naval tactics".
Edit this paragraph for test firing.
Beijing time 2065438+0065438+February 12 news, the powerful weapon developed by the United States-rail gun has taken another step towards success. In the test shot the day before yesterday, the navy hit an electromagnetic gun at a speed of five times the speed of sound at a target 200 kilometers away, with a range of 10 times that of conventional naval weapons. The destructive power is amazing, which is the best result of the test shot so far. The goal of the US military will be to conduct maritime surveys within eight years and formally equip warships before 2025. The US Navy tested electromagnetic guns twice at the surface warfare center in Dalgren, Virginia the day before yesterday. The electromagnetic gun is mainly composed of two tracks. The gun body is installed in a rectangular barrel the size of a trailer, and a 20-pound aluminum shell is placed in the middle of the track. After the electromagnetic gun is connected to the power supply, the current will pass through two tracks, thus generating strong thrust and ejecting the aluminum bomb at high speed. The energy produced by the two tests came from the tests of American electromagnetic guns.
It reached 33 MJ and 32 MJ, breaking the record of 10 MJ set in 2008. The energy of 1MJ is equivalent to 1T, and the power of the electromagnetic gun can be imagined. In addition to its power, the range of the shells fired by 33 MJ is 10 times that of conventional weapons, which is also a major advantage of electromagnetic guns. However, the ultimate goal of the US military's actual combat equipment is the 64 MJ electromagnetic gun, and its maximum range will reach 32 1km, allowing warships to launch attacks outside the range of enemy ships. The1600 million electromagnetic gun was put into the "Star Wars" program, which was once the key project of the US "Star Wars" armament program in the Cold War era and was regarded as a secret weapon against nuclear bombs. The US Navy restarted the research on electromagnetic guns in 2005, and has invested 211million dollars so far. Carl, director of the Naval Research Institute, said that electromagnetic guns have many advantages. First, the firing rate is fast, and there will be no problems such as target removal or failure like cruise missiles. With the Global Positioning System (GPS), the accuracy can be further improved. In addition, because the electromagnetic gun does not need gunpowder, it can not only improve the safety of the crew, but also increase the number of shells carried by the warship by 10 times. [ 1]?
reference data
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The electromagnetic gun tested by the United States is five times faster and has a range of 200 kilometers.
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Weapons knowledge, Youth Daily