Vibration analysis of rotating composite cylindrical shells with orthogonal stiffeners

Effect of boundary conditions on natural frequencies for rotating composite cylindrical shells with orthogonal stiffeners

A dynamic model for simulating rubbing between blade and flexible casing

Vibration and stability of pretwisted spinning thin-walled composite beams featuring bending–bending elastic coupling

Problems related with the implications of conservative and gyroscopic forces on vibration and the stability of a circular cylindrical shaft modeled as a thin-walled composite beam and spinning with constant angular speed about its longitudinal axis are addressed. Taking into account the directionality property of fiber reinforced composite materials, it is shown that for a shaft featuring flapwise-chordwise-bending coupling, a dramatic enhancement of both the vibrational and stability behavior can be reached. In addition, the effects played in the same context by transverse shear, rotatory inertias as well as by the various boundary conditions are discussed and pertinent conclusions are outlined.

Implication of conservative and gyroscopic forces on vibration and stability of an elastically tailored rotating shaft modeled as a composite thin-walled beam

The free and forced vibrations of rotating simply supported cylindrical shells are investigated. The equations of motion, which take into account the effects of initial tensions, are derived from Hamilton’s principle. The effects of rotation on the natural frequencies are first reviewed. Next, a new approach is developed for solving the general forced vibration response problem of rotating cylindrical shells. The solution in its final form is characterized by generalized coordinates. The orthogonality of trigonometric functions allows one to separate the solution such that the generalized coordinates associated with different rotational modes form a set of second‐order differential equations and can be solved for independently. The solution is further simplified for the cases where flexural vibration predominates. An inverted problem, where the cylinder is stationary and the load is rotating around it, is solved too for comparison. Finally, analytical solutions to the constant point load, and to the harmonic point load in the radial direction, are obtained using the developed method. The influence of rotation on the forced vibration is then illustrated.

W. Soedel

Papers

On the forced vibration of simply supported rotating cylindrical shells