Statistical analyses of a screen cylinder wake

• Published in: Fluid Dynamics Research
• Main Author: Azmi A.M.; Zhou T.; Zhou Y.; Cheng L.
• Format: Article
• Language: English
• Published: Institute of Physics Publishing 2017
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85009216649&doi=10.1088%2f0169-5983%2f49%2f1%2f015506&partnerID=40&md5=1746aed81df3cdb14011534e7c133123

The evolution of a screen cylinder wake was studied by analysing its statistical properties over a streamwise range of The screen cylinder was made of a stainless steel screen mesh of 67% porosity. The experiments were conducted in a wind tunnel at a Reynolds number of using an X-probe. The results were compared with those obtained in the wake generated by a solid cylinder. It was observed that the evolution of the statistics in the wake of the screen cylinder was different from that of a solid cylinder, reflecting the differences in the formation of the organized large-scale vortices in both wakes. The streamwise evolution of the Reynolds stresses, energy spectra and cross-correlation coefficients indicated that there exists a critical location that differentiates the screen cylinder wake into two regions over the measured streamwise range. The formation of the fully formed large-scale vortices was delayed until this critical location. Comparison with existing results for screen strips showed that although the near-wake characteristics and the vortex formation mechanism were similar between the two wake generators, variation in the Strouhal frequencies was observed and the self-preservation states were non-universal, reconfirming the dependence of a wake on its initial condition. © 2016 The Japan Society of Fluid Mechanics and IOP Publishing Ltd.