Low-Frequency Shielding Effectiveness of a Double Cylinder Enclosure

The low-frequency shielding effectiveness of a long double cylinder shield is determined through a solution of Maxwell's field equations. The shielding expression obtained is then compared with the results obtained by both the circuit approach and the transmission-line analogy. The findings of the present paper are also compared with the analysis by previous authors of the multishield problem. A digitalcomputer program for numerical evaluation of the effectiveness of adouble cylinder shield is developed and used to study the influence of the shield dimensions and material constants.