The effect of curvature and torsion of inclusions on effective permittivity of composite materials

We consider the problem of finding the effective dielectric permittivity of a fiber composite, accounting for curvature and torsion of inclusions. For this purpose, we adopt the Maxwell-Garnett approach based on the solution of the electrostatic problem for a single inclusion in a homogeneous electric field. It is assumed that the diameter of the inclusion is small in comparison with its radius of curvature and torsion. The electric potential is sought in the form of a series in powers of the distance to the inclusion. As an example of the results, the effective dielectric constant of the composite material with inclusions of a helical-line shape is investigated.