ICAP 2002 Abstracts and Posters

CTLSS-2: A 3D Conformal, Structured-Grid, Frequency-Domain Electromagnetic Simulation Code*

Abstract

CTLSS-2 is a three-dimensional, multi-block, non-orthogonal, structured-grid code that solves Maxwell's equations in the frequency domain both for resonant, eigenvalue problems and for non-resonant, driven-frequency problems. It represents a significant improvement over the original CTLSS code [1], which was restricted to orthogonal grids only. CTLSS-2 uses a conformal mesh, which provides greater accuracy and efficiency when modeling complex structures compared with the stairstep discretization of structures, and also improves the code's ability to handle wall losses and wall coatings. Use of a structured mesh allows greater control of the mesh topology than is possible with unstructured mesh, and permits studies involving geometry variations to be executed with minimal influence from fluctuating mesh parameters. The numerical formulation in CTLSS-2 is a hybrid of finite-element techniques for field integration and interpolation and a generalization of the Finite Integration Technique [2] to non-orthogonal grids. Iterative solution methods, based on the Jacobi-Davidson algorithm [3,4] for solving eigenvalue problems and on the Quasi-Minimal Residual (QMR) technique [5] for the inversion of large matrices, were retained from the earlier CTLSS to handle non- Hermitian operators that arise when treating lossy materials. This paper summarizes the underlying mathematical and numerical formulations for CTLSS-2, the results of validation test problems, and examples related to the scaling of solution accuracy with cell size.

* Work supported by the Office of Naval Research under Contract No. N00173-99-C-2043.

[1] S.J. Cooke, A.A. Mondelli, B. Levush, T.M. Antonsen, Jr., D.P. Chernin, T.H. McClure, D.R. Whaley, and M. Basten, "CTLSS – An Advanced Electromagnetic Simulation Tool for Designing High-Power Microwave Sources," IEEE Trans. Plasma Sci., Vol. 28, pp. 841-866, 2000.

[2] R. Schuhmann and T. Weiland, "The Non-Orthogonal Finite Integration Technique Applied to 2D- and 3D-Eigenvalue Problems," IEEE Trans. Magnetics, Vol. 36, pp. 897-901, 2000.

[3] G.L.G. Sleijpen and H.A. van der Vorst, "A Jacobi-Davidson Iteration Method for Linear Eigenvalue Problems," SIAM J. Matrix Anal. Appl., Vol. 17, pp. 401-425, 1996.

[4] S.J. Cooke and B. Levush, "Eigenmodes of 2D and 3D Electromagnetic Cavities Containing Absorbing Materials Using The Jacobi-Davidson Algorithm," J. Comp. Phys., Vol. 157, pp. 350- 370, 2000.

[5] R.W. Freund and N.M. Nachtigal, "QMR: A Quasiminimal Residual Method for Non-Hermitian Linear Systems," Numer. Math., Vol. 60, pp. 315-339, 1991.

R. Shtokhamer [a], S.J. Cooke [a], A.A. Mondelli [a], and B. Levush [b]. where, [a] Science Applications International Corporation, McLean, VA 22102 [b] Naval Research Laboratory, Washington, DC 20375

Go Back to the ICAP02 Talks Schedule page.
Go Back to the ICAP02 Posters page.
Go Back to the ICAP02 home.

This page is maintained by Kyoko Makino.