Comparative Analysis of the Muzzle Velocities of Projectiles in Horizontal and Inclined Configurations of the Coilgun

A coilgun is a type of electromagnetic launcher (EML) which can accelerate a projectile by converting electrical energy stored in high energy storage capacitors to kinetic energy of the projectile. In this paper, we analyze and compare the performance of a single stage coilgun in terms of the muzzle velocity of the projectile when the coilgun is fired in horizontal and inclined configurations. For the inclined configuration, the launch angle (angle of inclination) is taken as 45 degrees with the horizontal which shall give maximum range if air drag and friction are ignored. Inclined configuration is especially suitable for shorter range applications, wherein the launched objects need not escape the denser layers of atmosphere. The results are obtained using a commercially available FEM-based ANSYS ® Maxwell software. The electromagnetic force on the projectile in the inclined position is opposed by the component of weight of the projectile in the direction of motion resulting in reduced muzzle velocities. As the electromagnetic force on the projectile also depends on the rate of change of mutual inductance between the coil and projectile, a comparison of optimum initial position of the projectile in both cases is also made. An experimental single stage coilgun is also being developed in the lab to verify the results. Suitable arrangements will be required to keep the projectile at the optimum initial position before the coils are energized for inclined configuration to avoid sliding of the projectile due to gravity. These results will be helpful in optimal design of the induction coilgun used in certain applications.