The research about response of a circular cylinder with fairings hasbeen performed to control VIV previously, but not comprehensively. Inthe present study, the vibration of a circular cylinder with differentfairings(θ=120~0, 105~0, 90~0, 75~0, 60~0, 45~0, θ is the character angle offairings) was investigated experimentally in a wind tunnel. It was foundthat all the response here shows the typical VIV phenomenon, wherethe excitation was limited in a discrete range of velocities. The vortexshedding frequency also demonstrates the typical frequency lock-in.The attachment of fairings would lead to the expansion of initialbranch. When the character angle is large, the amplitude is slightlysmaller than that of circular cylinders. With the further decrease ofcharacter angle, the amplitude rises up again till θ=60~0. FFT spectrumsof velocity downstream show the coexistence of natural frequencycomponent and higher harmonics, which is related to vortex sheddingmodes. The fairings would induce frequent presence of high harmonics.
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