Transverse runout in flexible disk rotating at periodically varying angular speed

Under consideration of initial unstressed transverse runout, governing equation of a flexible disk rotating at periodically varying angular speed is modeled as a parametrically excited system, and steady state deflection and resonance of the disk is investigated by the harmonic balance method. The investigation shows that the initial transverse runout of a given disk mode affects the steady state deflection of the mode itself more prominently than other modes, and the deflection component fluctuating in high-frequency is weak and can be neglected in analysis. The disk resonates when the integer multiple frequency of angular speed variation around the disk natural frequency in the frame fixed on the disk. And each integer multiple frequency results in twin resonance peaks with increasing variation amplitude and constant part of the angular speed. The angular speed variation amplitude enlarges the resonance peaks.