Nonlinear optimization of the shape function in the finite element method when determining cutoff frequencies of waveguides of arbitrary cross section

摘要

The authors studied the k optimization process of the finite-element method when solving eigenvalue problems. The optimization process is then applied to the determination of the fundamental cutoff frequency of a waveguide of cardiodal cross section. It is shown that a considerable reduction in computer memory and/or CPU time is achieved by this process.