Dielectric polarizability of circular cylinder

This paper presents results from a numerical study of the polarizability characteristics of dielectric circular cylinders. Because no closed-form solution exists for the polarizability of cylinder, this quantity has to be calculated numerically. In the present article, this is done by solving the appropriate integral equation for the scalar potential when the cylinder is exposed to a static, uniform electric field. In the evaluation, Method of Moments solution is used along with third-order basis functions. The polarizability is calculated as function of the permittivity ε and the length-to-diameter ratio l/d of the cylinder, and it has two components, axial and transversal polarizabilities. The polarizability of the cylinder is close to that of a spheroid (ellipsoid of revolution) with the same ε and l/d. Since the polarizability of the spheroid is known and easily calculable in closed form, a very effective way of presenting the numerical results for the cylinder is to express the polarizability difference between these two objects as a function of the two parameters. The accuracy of the resulting estimates is better than 1 per cent.