form series solution of the mode shape. The
influence of mass per unit length on the natural
frequencies of a simply supported Rayleigh beam
freely vibrating has also been investigated. The
governing differential equation is solved and the
dimensionless natural frequencies for various values
of the mass per unit length of the beam were
obtained and presented in table. It was found that
the natural frequency of the beam decreases with
increase in the value of the mass per unit length. It is
recommended that the further studies on the
influence of rotary inertia on the vibration
characteristics of freely vibrating Rayleigh beam
should be carried out.
Nomenclature
Young’s modulus,
Moment of inertia of the cross section of the
beam
Mass per unit length of the beam,
Rotatory inertia of the beam
x spatial location along the beam
T time
Transverse displacement of the beam at
point
and time
.
L length/span of the beam
Circular natural frequency of harmonic
function of time
Modal deflection of the beam
Non-dimensional parameter of the spatial
location along the beam
Non-dimensional parameter of the
modal deflection of the beam
Non-dimensional parameter of the mass per
unit lenght of the beam
Non-dimensional rotary inertia
Acknowledgments:
The authors appreciate Covenant University for
supporting this research financially.
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WSEAS TRANSACTIONS on FLUID MECHANICS
DOI: 10.37394/232013.2022.17.17
Olasunmbo O. Agboola, Talib Eh. Elaikh,
Jimevwo G. Oghonyon, Olajide Ibikunle