A MODIFIED DIPOLE-ENHANCED APPROXIMATION FOR A DIELECTRIC SPHERE

In this paper, a modification of the previously developed dipole-enhanced approximation for merging spheres in a dielectric mixture has been carried out. In this modified dipole-enhanced approximation, the equivalent enhanced field experienced by an arbitrarily selected sphere is related not only to the difference in permittivity and the ratio of the sphere’s radius to the average distance between neighbor spheres, but also to the position of the field point. It is acceptable for the calculation of local electric field strength in a dielectric mixture with a large dielectric mismatch and a high-volume fraction of spheres or long cylinders. The electric field distributions calculated by this model on the surface of a sphere or the circumference of a circle are compared with those obtained with the dipole model, the previous dipole-enhanced model and the finite-element method, which shows that this kind of approximation is reasonable and much better than the previous dipole-enhanced model and the dipole model.