A dipole-enhanced approximation for a dielectric mixture

This paper presents a dipole-enhanced approximation to calculate the saturation charge of particles for high-volume fraction particles. An approximate formula for calculating the maximum field strength at the surface of one sphere is derived. It shows the variation of the maximum field strength with the difference in permittivity and the ratio of the particle radius to the distance between particles. The maximum field strengths calculated using this formula are compared with those obtained with the dipole model and the finite-element method, the calculated result shows that the formula is acceptable. A formula for calculating saturation charge of particles is derived, which depends on the volume fraction of particles.