Finite-difference method on electrostatics field calculation in oil storage tank

This paper starts with the basic principle of Finite-Difference Method, combined with the practical application of the method, focusing on the difference scheme of Poisson equation and Laplace equation in 2D Electric Field and Axisymmetrical Field under the square grid partition. This study solves the Finite-Difference Method on electrostatics field calculation and introduces discretization on the Dirichlet Problem in oil storage tanker. The Finite-Difference Method gives the analytic solutions of the potential equations by changing the continuous field problems into discrete system. The numerical solutions of discrete points could infinitely approximate the real solution of the continuous field through discrete model.