ON THE FREE-VIBRATIONS OF MULTIPLE PLATES WELDED TO A CYLINDRICAL-SHELL WITH SPECIAL ATTENTION TO MODE PAIRS

The modal characteristics of circular plates welded or riveted to the great circles of a cylindrical shell were studied using the receptance method. The methodology was generalized to a system which is composed of k plates and one shell. As example, the practically important case of k = 2 is presented and studied in detail. In this paper the effects of radii, lengths and joining positions on the dynamic behavior of the combined structure are studied, and an interesting tuning and detuning phenomenon involving the two plates, which is sensitive to component stiffness changes, is investigated. The results obtained by using the receptance method are verified with those obtained by using the finite element method, and natural frequencies and mode shape behavior of the plate-shell structure under different joining configurations are illustrated in detail. The motivation for the research was to understand the dynamic behavior of such a system in terms of the behavior of its components, in order to provide useful design synthesis criteria. © 1993 Academic Press Limited.