Travelling Wave Multipole Field Electromagnetic Launcher: An SOVP Analytical Model

The problem of the evaluation of eddy currents induced in a conductive cylinder is, here, reconsidered under the light of possible application in the electromagnetic launch context. In particular, we derive an analytical solution when the system is excited by a sinusoidal current flowing in a saddle coil moving in the axial direction. Subsequently, we consider an arrangement of such coils distributed in the axial and azimuth direction. When properly fed, they produce a travelling wave of flux distribution, which is able to exert a thrust force on the conductive cylinder. Since the governing vector field equation is not separable in the cylindrical coordinates, an approach based on the second-order vector potential formulation has been, here, adopted. Scalar field equations are obtained whose solutions are expressed in terms of Bessel functions.