An efficient method for solving electrical constriction resistance of rough surfaces

An efficient method is presented to solve the electrical constriction resistance (ECR) in electrical contact problem. For two contact parts under a specified total current, the conjugate gradient algorithm is proposed to determine the unknown current density in contact region. Two variations of discrete convolution-fast Fourier transform algorithm are used to solve the electrical potential for contact parts of finite and infinite size, then the ECR can be obtained. These algorithms lead to an efficient method, which is verified by finite element analysis and analytical formulas. Compared with widely used methods for estimating ECR, the present method shows broad applicability in diverse surfaces by considering both shapes and interactions of contact spots, and has capacity to capture the solution details.