Deformable, time-varying boundary problems in electrodynamics

A novel perturbation technique is formulated that enables the efficient calculation of current on surfaces undergoing time-varying mechanical deformations. The technique computes the current on the perturbed surface using as its starting point the solution for a related static case. This is initially derived using a standard analytical or numerical technique. The key advantage of this approach is that only an initial (computationally expensive) electromagnetic characterisation of the static problem is required. The surface current perturbation terms (and hence the radiated fields) are then directly computed from the static problem with a very low computational overhead.