1. College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China
2. Wenzhou Electric Power Company, State Grid Corporation, Wenzhou 325000, China
Abstract：In order to study aeolian noise generated by a smooth circular cylinder under different wind speed conditions, an acoustic wind tunnel was built to conduct aeolian noise tests of rod system type structures. The wind tunnel tests for circular cylinders of 11 diameters were conducted under 4 wind speeds. The frequency spectra’s characteristics and dominant frequencies of aeolian noises generated by circular cylinders were analyzed. Finally, the variation laws of accumulative dominant sound pressure levels and dominant frequency band widths with varying wind velocity and Reynolds number were investigated. Results showed that dominant frequencies of wind noises generated by circular cylinders are proportional to wind speed and inverse proportional to diameter of circular cylinder; Strouhal number calculated from dominant frequencies within Reynolds number range of 3e3-1e5 is about 0.20, it has a gradually decreasing trend with increase in Reynolds number; the accumulative dominant sound pressure levels increase with increase in Reynolds number, they disperse more within a lower Reynolds number range of less than 3e4, and less within a higher Reynolds number range.
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