volume | PIER Journals

Abstract

This paper investigates, by means of finite-element simulations, how the position of an aperture affects the electrostatic shielding effectiveness of a rectangular metallic enclosure. First, we compute the electric-field distribution on the surface of a completely closed enclosure placed in an external electric field. The results show that, for every wall, the field is weakest at the center, and that the field on walls parallel to the external field is far lower than that on walls perpendicular to it. Next, we determine the electric field that leaks into the enclosure after an aperture is introduced. We find that the field strength decreases with the distance from the aperture, that the field near the aperture is proportional to the surface field at the aperture's location when the aperture is covered. Also, its magnitude can be predicted by the classical model of the small aperture coupling. Finally, we investigate the coexistence effect and formulate guidelines for choosing the aperture position to achieve optimum shielding performance.

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Dr. Xiaolin Zhao

Dr. Hanyu Wu

Professor Chongqing Jiao