E-M field between moving rugous surfaces

E-M field between moving rugous surfaces

Variable capacity effect induced by loss of contact between two rugous plane surfaces (from two cylinders, by axial symetry: see full 3D model below)

The animation shows one complete harmonic of the movement, when one surfaces (cylinder) translate w.r.t. the other, which modifies the E-M field in the gap hence a variable capacity.