The document discusses the railgun, including its history, key parts, operating principles, and applications. A railgun uses electromagnetic force to launch high-velocity projectiles by passing high-current electricity through a conductive armature between two parallel conducting rails, producing a magnetic field that accelerates the armature along the rails. Railgun research and development aims to increase firing rates and projectile velocities for applications in weapons, space launch systems, and fusion energy. Challenges include managing thermal stresses on rails and reducing the size of required power supplies.

1. RAILGUN

2. OVERVIEW
 What is Rail gun
 History of Rail gun
 Parts of Rail gun
 How does its work
 Basic physics of Rail gun
 Current Research and Development
 Physics of Rail gun
 Applications of Rail gun
 Advantages / Disadvantages
 Long/ Short term goals

3. • The EM Rail gun is an electrically powered
electromagnetic projectile launcher.
• As its name shows “gun in which a pair of rails is
used”.
• It is an entirely electrical gun that accelerates a
conductive projectile along a pair of metal rails
using the same principles as the homopolar motor.

4. HISTORY OF RAILGUN
• First Railgun idea was given by French inventor
Louis Octave in 1918 by designed an electric
cannon.
• In world war 2, the German commander Luftusaffe
issued a specification for a Railgun based anti-
aircraft gun.
• The first Railgun is tested in 1970 at the Australian
National University.
• In 2003, Ian Nab plans to built a system to launch
supply into space using Railgun Technology.

5. Parts of Rail gun
• A rail gun is basically a
large electric circuit,
made up of three parts:
a power source, a pair
of parallel rails and a
moving armature.

6. • The power supply is simply a source of electric
current. Typically, the current used in medium- to
large-caliber rail guns is in the millions of amps.
• The rails are lengths of conductive metal, such as
copper. They can range from four to 30 feet (9
meters) long.
• The armature bridges the gap between the rails. It
can be a solid piece of conductive metal. Some rail
guns use a plasma armature. In this set-up a thin
metal foil is placed on the back of a non-conducting
projectile. When power flows through this foil it
vaporizes and becomes a plasma, which carries the
current.

10. How the pieces of Rail gun work
• An electric current runs from the positive terminal of the power supply, up the positive rail,
across the armature, and down the negative rail back to the power supply.
• Current flowing in any wire creates a magnetic field around it -- a region where a magnetic
force is felt. This force has both a magnitude and a direction. In a rail gun, the two rails act
like wires, with a magnetic field circulating around each rail. The force lines of the magnetic
field run in a counterclockwise circle around the positive rail and in a clockwise circle around
the negative rail. The net magnetic field between the rails is directed vertically.
• Like a charged wire in an electric field, the projectile experiences a force known as
the Lorentz force (after the Dutch physicist Hedrick A. Lorentz). The Lorentz force is directed
perpendicularly to the magnetic field and to the direction of the current flowing across the
armature.
• the Lorentz force is parallel to the rails, acting away from the power supply. The magnitude
of the force is determined by the equation F = (i)(L)(B), where F is the net force, i is the
current, L is the length of the rails and B is the magnetic field. The force can be boosted by
increasing either the length of the rails or the amount of current.

11. HOW DOES IT WORKS ?
• When the projectile is inserted between rails, it complete
circuit.
• When supply is given to the rails behaves as an
electromagnet, creating a magnetic field inside the loop
formed by length of rails up to the position of armature.
• According to the right hand rule magnetic field circulates
around each conductor.
• Due to net magnetic field in rails (B) is directed at right angle
to the plane formed by central axis of the rails and armature,
in combination with current (I) in the armature.
• This produce Lorentz force which accelerates the projectile
along the rails.

12. Current research and devlopment

13. Physics of Rail Gun
• Rail gun theory is based on
the Lorenz force phenomenon
• When a wire carrying an
electrical current is placed in a
magnetic field, each of the
moving charges, which
comprise the current
experiences the Lorenz force
and together they can create a
macroscopic force on the
wire, which is expressed as-
F= ILB

18. APPLICATIONS
• As weapon in modern warfare:-
- First military railguns will be produced for next
generation of cruisers
- Projectiles using kinetic energy to destroy target
- Range of railgun 2-3 times bigger than standard
technologies (Medium Range Missiles) and 10 times
bigger than naval cannons
• Trigger for Inertial Confinement Fusion.
• Launch or launch assist of spacecraft

19. ADVANTAGES
• The railgun has a much larger possible power than a powder
gun.
• Currently, we have been able to reach velocities around 9
km/s with the railgun; whereas, the maximum velocity a
powder gun can reach is less than 8.5 km/s. It is believed that
the railgun can reach up to 140 km/s.
• Since the railgun depends entirely on a massive current, there
is no need for fuel or explosives. This is more efficient in three
ways:
- The risk is greatly reduced for the sailors handling the
weapon system.
- The weight of the entire system is reduced.
- The smaller size frees up a lot of space, which is crucial on
cramped battleships.

20. DISADVANTAGES
• One of the biggest problems is with maintaining the
structural integrity of the rails as they undergo such
stressful conditions.
• The thermal management of the entire system,
especially as the rails increase in size needs to
improve.
• The pulsed power unit and supply could be
compacted and decreased in size, as it encompasses
most of the system.
• Power supply too big and heavy- needs 3-story
building and there is no commercial interest.

21. LONG TERM GOALS
- Fully electric destroyers and battleships.
Modified electromagnetic railguns outfitted for aircraft.
- Small battery packs that are powerful enough to power handheld.
- Launch assist system for space craft.
SHORT TERM GOALS
- Increase the fire rate of the current prototype up to ten rounds per
minute.
- Find a more efficient combination of metal conductors for the rails
and for the armature.

22. REFERENCES….
• Fletcher, Seth (2013-06-05). "Navy Tests 32-Megajoule Railgun
|". Popular Science. Retrieved 2013-06-16.
• ^ Rashleigh, C. S. & Marshall, R. A. (April 1978). "Electromagnetic
Acceleration of Macroparticles to High Velocities". J. Appl.
Phys. 49 (4): 2540. doi:10.1063/1.325107.
• ^ "Rail Strike". The Economist. 2015-05-09. Retrieved 2016-01-31.
• ^ Atkinson, Nancy (2010-09-14). "NASA Considering Rail Gun
Launch System to the Stars". Universe Today.
• ^ Hindmarsh, John (1977). Electrical Machines and their
Applications. Oxford: Pergamon Press. p. 20. ISBN 0-08-021165-8.
• ^ Fiske, D.; Ciesar, J.A.; Wehrli, H.A.; Riemersma, H.; et al. (January
1991). "The HART 1 Augmented Electric Gun Facility". IEEE
Transactions on Magnetics 27