T-E formulation-based modeling of thin HTS shell magnetization

TL;DR

This paper extends a T-E formulation-based finite element method for modeling magnetization in thin superconducting shells, including non-flat geometries, validated through tests and applied to a dynamo pump simulation.

Contribution

It introduces an extension of the T-E formulation method to non-flat superconducting shells with validation and practical application.

Findings

Validated the extended method with test examples including a sphere.

Successfully modeled a cylindrical magnetic dynamo pump and computed voltage.

The method accurately captures complex geometries without surrounding space meshing.

Abstract

Numerical methods for modeling thin-film magnetization are primarily focused on computing the current density distribution. The highly nonlinear current-voltage characteristic of type-II superconductors significantly complicates the accurate computation of the electric field. The T-E formulation-based mixed finite element method, previously derived for flat superconducting films, enables the simultaneous, accurate determination of both variables. Another advantage of this method is that the computational domain is limited to the film itself: no meshing of the surrounding space is required. The thin-shell approximation reduces the problem to a two-dimensional one. This work extends the T-E formulation and numerical method to non-flat superconducting shells with a metal substrate. We validate the method with several test examples, including modeling the magnetization of a sphere. The method is then applied to a realistic model of a cylindrical magnetic dynamo pump, and the generated open-circuit voltage is computed.