“…These studies concluded that the natural frequencies of flexural vibration tended to increase above those for the non-rotating beams, because of the centrifugal force and the subsequent stiffening effects [1]. The free vibration analysis of rotating beams have been widely studied using different numerical approximation methods, such as, the Rayleigh or Rayleigh-Ritz methods [1,2,3,4,5], the finite element method [6,7,8,9,10], the differential transform method [11] and Galerkin's method [12]. Moreover, AL-Said et al [13,14] analysed the free vibration of a Timoshenko beam modelled by a massless torsional spring, to simulate the flapwise vibration of a thick rotating beam.…”