Summary: | 碩士 === 國立中央大學 === 土木工程研究所 === 87 === This study experimentally investigated the wake flow around a two-dimensional square cylinder that was placed in a uniform shear flow. Velocity and turbulence properties behind the cylinder were measured by a two dimensional thermal anemometer. The measured turbulent velocity and vorticity distribution were analyzed by a phase-average technique. The experimental results revealed that the turbulence intensity, Reynolds stress, turbulent kinetic energy and vorticity all have asymmetric distribution in the wake flow. The difference between the upper and lower vorticity is larger than the upstream vorticity. Also, the peak vorticity has a periodic variation, but decays as the downstream distance increases. Results of the study can improve our understanding of vortex structure in non-uniform flows.
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