Author: John L. SewallPublisher:
ISBN:
Category : Frequencies of oscillating systems
Languages : en
Pages : 92
Book Description
This paper reports an experimental and analytical vibration study of free-free isotropic elliptical cylindrical shells of constant mass ranging in cross-sectional eccentricity from zero (circular shell) to 0.916. Experimental resonant frequencies, nodal patterns, and mode shapes were obtained by use of an air-jet shaker or an electrodynamic shaker with a noncontact inductance probe that could be moved over most of the shell surface. Experimental frequencies were in generally good agreement with analytical frequencies calculated by means of a Rayleigh-Ritz type of analysis featuring multiterm longitudinal and circumferential modal expansions. Frequencies for shells with eccentricity of 0.916 were as much as 40 percent below the corresponding circular-shell frequencies. As eccentricity increased, analytical and experimental mode shapes indicated considerable longitudinal and circumferential modal coupling.
