ELECTROMAGNETIC RAILGUN

Railgun are one of the potential game changing weapon of the future war.Railgun use electromagnetic force to launch high velocity projectiles.Instead of use of chemical explosive such as gun powder it uses electromagnetic force to propel projectile to hyper sonic speed potentially into a range of several hundred miles.The railgun uses a pair of parallel conductors, or rails, along which a sliding armature is accelerated by the electromagnetic effects of a current that flows down one rail, into the armature and then back along the other rail. Railgun relying on the projectile's high speed to inflict damage.

The most commonly used way of projection in military, by means of gunpowder, has many disadvantages including additional weight, volatility and limited velocity. This fact enhanced scientists to look for more efficient way to launch projectiles. The electromagnetic rail gun has appeared as a promising propellant with a velocity of 16,000 m/s, about 12 times that of gunpowder, and a range of about 400 km. These features are so attractive to the extent that the concept of launching projectiles with electric energy was introduced more than 90 years ago.

"A rail gun is a purely electrical gun that accelerates a conductive projectile along a pair of metal rails". It contains two parallel metal rails with a sliding conductive armature.The acceleration of the projectile, which is driven be the armature, is achieved by a power supply acting mainly as a current source and providing a huge current.

DESIGN

 PROBLEMS WITH RAIL GUNS

In theory, rail guns are the perfect solution for short- and long-range firepower. In reality, they present several serious problems:

Power supply

 The power supply that use in rail gun must provide large current.Generating the power necessary to accelerate rail gun projectiles is a real challenge.Here capacitor is use for store the charge. This Capacitors must store electric charge until a sufficiently large current can be accumulated. While capacitors can be small for some applications, the capacitors found in rail guns are many cubic meters in size.

Resistive heating

 When an electric current passes through a conductor, it meets resistance in the conductive material -- in this case, the rails. The current excites the rail's molecules, causing them to heat. In rail guns, this effect results in intense heat.

 Cooling techniques should be used effectively to prevent intense heating. In addition, materials used to build rail guns have to be chosen such that it gives optimum resistance to heating.

APPLICATION

This devastating weapon currently in developing phase. This weapon attain attention of the several countries. It have number of practical application in the military field as this weapon will primarily use by the military.

Railguns are being examined for use as anti-aircraft weapons to intercept air threats, particularly anti-ship cruise missiles, in addition to land bombardment. A railgun projectile can reach several times the speed of sound faster than a missile; because of this, it can hit a target, such as a cruise missile, much faster and farther away from the ship.The speed, cost, and numerical advantages of railgun systems may allow them to replace several different systems in the current layered defense approach.

US first successfully develop this  railgun. Recently india successfully tested their own railgun. India`s DRDO successfully tested this but the developement is still going on. Russia, China ,Turkey also developing this railgun to strengthen their army.