INSTANTANEOUS-ADVECTIVE STRUCTURES OF LARGE SCALE COHERENT VORTICES AROUND A SINGLE GROYNE
Studies on flow patterns and transport process around groyne-like structures have recently and significantly increased related to improved experimental and computational possibilities.However, only few studies focus on flow in wide flow-area and also variations of water level,especially the case of submerged groynes. To investigate the instantaneous flow patterns around a single groyne, experiments were conducted by means of surface flow visualization technique in the shallow water channel. A Particle Tracking Velocimetry (PTV) method is adopted and implemented in order to calculate velocity fields fast and accurately. A 2D-PTV code was programmed by combining the advantages of FFT and Direct Correlation methods to get accurate results within reasonable time. In addition, Proper orthogonal decomposition (POD) is applied to obtain an impression of the fluctuating flow pattern and its coherent structures. Conditional sampling analysis is also applied to reveal the advection properties of POD decomposed flow pattern. The present study discusses the turbulence statistics; POD decomposed coherent patterns and their advection properties under submerged and emerged conditions. The results of POD pattern and advection clearly highlight the typical fluctuating flow pattern and large-scale motion, respectively.
shallow flow visualization particle tracking velocimetry proper orthogonal decomposition (POD) conditional sampling analysis
Akihiro Kadota Eiji Kojima Kenzo Shinya Koichi Suzuki
Department of Civil & Environmental Engineering, Ehime University,Matsuyama, Ehime 790-8577, Japan
国际会议
第16届亚太地区国际水利学大会暨第3届水工水力学国际研讨会(16th IAHR-APD Congress and 3rd Symoposium of IAHR-ISHS)
南京
英文
1137-1142
2008-10-20（万方平台首次上网日期，不代表论文的发表时间）