著者

辻 義之 宮地 圭 鈴木 孝裕 中村 育雄

出版者

日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.70, no.695, pp.1679-1686, 2004-07-25

参考文献数

17

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In a zero-pressure gradient turbulent boundary layer, the multi-point measurement by 24 ch I-probes is performed. The relation between coherent structures and logarithmic velocity profile is studied by way of proper orthogonal decomposition technique and the stochastic estimation. It is found that the existence of coherent structures are necessary condition for the universal velocity profile, however it is not enough. Small-scale motions are also necessary to realize the log-law profile. The probability density profile in the overlap region is studied, and as a result, the invariant assumption of PDF in relation to the coherent structure is obtained. It was also evaluated how the velocity fluctuation in the log-region is affected by the coherent structures.