Method for calculating electrostatic fields with axial and transaxial symmetry

Method of calculation electrostatic fields with axial and transaxial symmetry based on the decomposition potential into two terms. The main component is a harmonic function of two variables η = ln(ρ / ρ 0) and z, satisfying the given boundary conditions. Harmonic component of the potential is analytically using methods TFCV. The second term is the solution of the inhomogeneous equation with homogeneous Dirichlet boundary conditions and can be found numerically with the required accuracy.