2004 Volume 48 Pages 805-810
The flow structures around the continuous spur dikes were investigated by using a PIV method. In this study, the orientation angle of spur dike was chosen as a control parameter and it was varied in three ways. The visual images were recorded by a high-speed camera and analyzed with the cross-correlation method. Combining the two-dimensional PIV analysis of horizontal and vertical planes, we were able to verify the time-averaged three-dimensional flow structures. In the forefront section, obvious differences were observed among the three cases. The flow structure in the second spur-dike zone is controlled by the interaction with the separated flow from the first spur dike. In the backward section, the flow deflection as seen in the forefront section was not observed, but still slight differences are recognized. Particularly, the over flow velocity on the downstream-oriented spur dike becomes much larger than that in the other cases.
