Improved finite element method based on radial point interpolation method (RPIM) for electro-thermal coupling

Abstract

Efficient electro-thermal coupling calculation is of great significance to the monitoring and structural design of power equipment. Finite element method (FEM) is one of the powerful tools of electro-thermal analysis and is widely used in various fields. However, the finite element method itself cannot solve the first-order discontinuity, which causes the deterioration of accuracy. For example, in the electro-thermal coupling calculation, Joule heat is often used as the only heat source of the thermal field, and the calculation of Joule heat depends on the first-order variable field strength of the electric field. The calculation error of is further amplified in the thermal field solution, and the performance is more obvious in strong electromagnetic environment. Therefore, this paper proposes a finite element (RFEM) electrothermal coupling method based on the radial point interpolation method (RPIM). The idea of this method is to use the first-order continuous RPIM method to interpolate the variables in the overall solution domain to obtain continuous and smooth solution results. Examples show that RFEM has a higher solution efficiency than FEM, and it is better at capturing local high gradient changes in an electromagnetic environment.