Surface oscillations in flow past a side cavity using stereoscopic measurement and POD

Tsubaki Ryota

Fujita Ichiro

Journal of hydroscience and hydraulic engineering

When a relatively large side cavity is created in an open channel, the influence of vortices in the shear layer and circulatory flow is exerted on the main flow, causing surface oscillations and increased water levels. The mechanism of the oscillation is still not clearly understood because of the complexity of the phenomena. In this research, by using a stereoscopic surface measurement system developed by the authors, time-dependent water surface configurations are successfully measured at a sampling rate of 12 Hz, from which general features of the surface oscillation are made clear for a wide range of Froude numbers. Then, we applied the proper orthogonal decomposition (POD) method to measure results. We found that the surface oscillation can be clearly decomposed into a seiche-like major mode and sub-modes with smaller wavelengths.

Construction. Civil engineering [ 510 ]

eng

土木学会水理委員会

(c) 2006 公益社団法人 土木学会. All rights reserved.

[ISSN] 0912-2508

[NCID] AA1045915X

[URI] http://www.jsce.or.jp/publication/e/book/book_jhhe.html#242