控制和减少“丁坝”下游回流尺度的试验研究

由于流动边界出现凸出障碍物引起边界层分离，导致回流发展，水流流态恶化等，采用吸、喷水方法，在凸出障碍物与水流平行的边界略上部位将边界层水流吸走，并在其下游喷水，以减小回流范围和强度，水槽试验表明，吸、喷水量为水槽中总流量的1．5％－2％时，回流长度将减小70％－80％。

Experimental study on reducing the size of circumfluencedownstream of spur dikes

Boundary layer is separated for the barrier along the flow border line, thus the circumfluence is strengthened and the flow pattern deteriorated. Using the method of sucking spouting water, namely, sucking part of the discharge in the upstream of the convex barrier and spouting it downstream, can reduce the intensity and size of circumfluence. The results of flume tests show that a suitable sucking spouting discharge (1 5%-2% of the whole discharge) can cut the length of the circumfluence down to 20%-30%.