The effect of pulsations superimposed on a mean incident flow on the streamwise vibration of an elastically-supported cantilevered rigid cylinder with two coupled translational and rotational degrees of freedom was investigated experimentally. The pulsation frequency was varied between 7.8–19.2 Hz corresponding to 1.2–3.0 times the vortex shedding frequency from a fixed cylinder in steady flow whereas the amplitude of the pulsations and the incident-flow mean velocity were held constant, the latter corresponding to a Reynolds number of 2160. The results show that there are two excitation regions in which the amplitude of vibration increases up to 400% compared to that in steady flow at the same Reynolds number. As the pulsation frequency is further increased in each range, the amplitude of the vibrations drops almost linearly down to a level near that without flow pulsations although the frequency of vibration remains locked-on at the imposed pulsation frequency in all cases.

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