Application Of Electromagnetic Energy,Momentum and Kinetic Energy In The Superweapon Called The Hypersonic Railgun
When you think Super-weapons, what comes to mind?
Nuclear Bombs? Automated bullets? Cool..
Or maybe you start to remember all of the outlandish weapons that James Bond always kept at his side?
Or, how about all the space-age wonders that were used in great battles on Star Trek or Star Wars?
While we sci-fi fans were in awe of these marvels of weaponry, we always knew in the back of our minds that it was all fantasy but with today’s advanced computer technology, those far-out gadgets are not as impossible as we once thought.
It's about time you added The Hypersonic Railgun to your superweapon list.
What the heck is The Hypersonic Railgun?
A railgun is a device that uses electromagnetic force to launch high velocity projectiles, by means of a sliding armature that is accelerated along a pair of conductive rails.
Hypersonic implies it attains speeds of more than five times the speed of sound (Mach 5).
It is typically constructed as a weapon and the projectile normally does not contain explosives, normally relying on the projectile's high speed to inflict damage.
To get a grasp of what a missile relying on it's massive kinetic energy to cause damage can do, Check out this excerpt from G.I. Joe: Retaliation - Project Zeus's Demonstration
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In the way that cannons use gunpowder to launch a projectile, railguns use electromagnetic energy, essentially giving them the speed of a cannon with the range of a missile, according to Popular Science. The “rail” part refers to the weapon utilizing two rails with a powerful electromagnetic field generated in between. The gun’s armature, meaning an electricity-conducting device made out of metal, shoots the projectile out through the field between the two rails, according to Popular Mechanics
So, How Does It Work?
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.
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 or a conductive sabot -- a carrier that houses a dart or other projectile. 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.
Here's how the pieces work together:
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 Hendrik A. Lorentz). The Lorentz force is directed perpendicularly to the magnetic field and to the direction of the current flowing across the armature. You can see how this works in the diagram below.
Notice that the Lorentz force is parallel to the rails, acting away from the power supply. The magnitude of the force is determined by the equation
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.
Because long rails pose design challenges, most rail guns use strong currents -- on the order of a million amps -- to generate tremendous force. The projectile, under the influence of the Lorentz force, accelerates to the end of the rails opposite the power supply and exits through an aperture. The circuit is broken, which ends the flow of current.
Applications
Obviously, Weaponary:
The United States Navy has been developing its own railgun technology for almost a decade now, according to New Scientist. While the U.S. system would be land based, as opposed to mounted on a Navy landing craft as the Chinese railgun appears to be, it’s however a formidable weapon nonetheless.
The U.S. Navy’s railgun can fire a projectile at a speed of more than 4,500 miles per hour, which corresponds roughly to Mach 6. Its goal is to exceed a projectile range of 100 miles, which would mean that, power-wise, each shot would expend the same amount of energy needed to power about 19,000 homes.
"Railguns and other directed-energy weapons are the future of maritime superiority," Dr. Thomas Beutner, head of ONR's Naval Air Warfare and Weapons Department said at the Naval Future Force Science and Technology Expo. "The U.S. Navy must be the first to field this leap-ahead technology and maintain the advantage over our adversaries."
Plans were in place to ensure Railgun rep-rate testing was at 20 mega-joules by the end of 2017 and at 32 mega-joules by 2018, an ONR release stated.
To put this in perspective, one megajoule is the equivalent of a one-ton vehicle moving at 160 miles per hour.
To make this weapon more lethal, Defense Systems arent really developed to ward off impeding attacks.
Though The US Navy plans for railguns to be able to intercept endoatmospheric ballistic missiles, stealthy air threats, supersonic missiles, and swarming surface threats; a prototype system for supporting interception tasks is to be ready by 2018, and operational by 2025.
“There isn’t really a known defense mechanism against a railgun shot at high Mach numbers,” Justin Bronk, a combat technology researcher at the Royal United Services Institute in the United Kingdom, told New Scientist. “It’s too fast and too small for current anti-ship missile and anti-aircraft defense systems....If they can get it integrated as a major component into their future fleet arsenal, it will give them a really significant edge over the U.S. Navy."
Can be used as a Space Gun
A Space Gun is a method of launching an object into space using a large gun- or cannonlike structure. Space guns could thus potentially provide a method of non-rocket spacelaunch.
In Project HARP, a 1960s joint United States and Canada defence project, a U.S. Navy 16 in (410 mm) 100 caliber gun was used to fire a 180 kg (400 lb) projectile at 3600 m/s or 12,960 km/h (8,050 mph), reaching an apogee of 180 km (110 mi), hence performing a suborbital spaceflight.
However, a space gun has never been successfully used to launch an object into orbit or out of Earth's gravitational pull because these speeds are too far into the hyper-sonic range for most practical propulsion systems and also would cause most objects to burn up due to aerodynamic heating or be torn apart by aerodynamic drag.
A more likely future use of space guns would be to launch objects into near Earth orbit, from where attached rockets could be fired or the objects could be "collected" by maneuverable orbiting satellites.
Hurdles? Yep.
While railguns show much promise for the future, there are major hurdles to overcome before such weapons are ready for prime time.
One Major challenge is Rail Durability in that the US Navy has not yet developed a barrel that can withstand repeated firings over a certain period of time.
In a March 2014 statement to the Intelligence, Emerging Threats and Capabilities Subcommittee of the House Armed Services Committee, Chief of Naval Research Admiral Matthew Klunder stated, "Barrel life has increased from tens of shots to over 400, with a program path to achieve 1000 shots." However, the Office of Naval Research (ONR) will not confirm that the 400 shots are full-power shots.
According to an article by Globalsecurity railguns should be able to fire 6 rounds per minute with a rail life of about 3000 rounds. Tolerating launch accelerations of tens of thousands of g's, extreme pressures and mega-ampere currents over this sort of duty cycle is currently beyond the state of the art.
The Navy also has to develop power sources that can supply energy to electricity intensive weapons.
Plans are however in motion to overcome these limitations.
So, what are your thoughts? I'd love to know
Thanks
References
Wikipedia
Newsweek
National Interest
How Stuffs Work
Image Credits
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