Numerical simulation of heat transfer in underground electrical cables

Abstract

The aim of this project is to develop a virtual modelling tool which can be used to construct optimal design of power transmission lines and cables. They should meet the latest power transmission network technical and economical requirements. The mathematical model is based on a general heat conduction equation describing the diffusion, convection and radiation processes. We take into account a linear dependence of the resistance on temperature. The velocity of convective transport of the heat in air regions is obtained by solving a coupled thermoconvection problem including the heat conduction problem and a standard Navier-Stokes model of the flow in air. The changes of material coefficients in soil due to influence of heating are taken by solving a simplified mass balance equation for flows in porous media. The FVM is used to solve the obtained system of differential equations. Discretization of the domain is done by applying “aCute” mesh generator, which is a modification of the well-known Triangle mesh generator. The discrete schemes are implemented by using the OpenFOAM tool. Parallel versions of basic algorithms are also investigated. Results of computational experiments of simulation of real industrial underground cables are presented.