An adaptive meshless method for magnetic field computation

Design of electromagnetic (EM) actuators often involves solving a magnetic field problem. This paper presents an adaptive meshless method (MLM) that inherits many advantages of the finite-element method (FEM) but needs no explicit mesh structure for design of EM actuators. Specifically, the paper offers a technique to estimate the distribution of numerical errors and a scheme that automatically inserts additional nodes to improve computational accuracy and efficiency. It gives several examples. The first three numerical examples, where exact solutions are available, provide a means to validate the adaptiveMLM and evaluate its effectiveness against a regular MLM with a uniform node distribution. The other examples, where magnetic forces are computed from Lorenz’s law, illustrate the use of adaptive MLM for practical design of an EM actuator. The paper compares the computed forces against published experimental results.

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