The Electromagnetic Fields from a Railgun

A Railgun is a type of magnetic accelerator gun that utilizes an electromagnetic force to propel an electrically-conductive projectile. Current flowing through the rails sets up magnetic fields perpendicular to each other, forcing the projectile to accelerate along the rails.

As no ferromagnetic materials are involved, there are no saturation effects and the muzzle speed of the projectile is only limited by the available electric power and the structural and thermal durability of the device. In theory, muzzle speeds of several km/s are possible.

This 3D model is solved using a transient inductive formulation for the electromagnetic part coupled to an ordinary differential equation for the lumped kinematics of the armature.

Boundary plot showing the electric potential on the rails and streamline plot showing the magnetic flux density, illustrating the movement of the projectile along the rails.

Animated Model