Abstract: Flow features of sharp bend in mountain river are investigated in this article. The theorectical relationships to predict the rise in the upstream flow depth and maximum width of backflow zone are derived on the basis of the energy and momentum principles. The proposed relationships are verified by the results of experiments for a right-angled sharp bend. It shows that the depth rise and maximum width of backflow zone depend on froude number and bend angle. And the explicit approximate relationships for calculating the depth rise and maximum width of backflow zone are presented.

Key words: sharp bend, depth rise, backflow zone

摘要： 对山区河流折角急弯段的基本特征进行了研究. 根据能量和动量守恒原理, 导出了计算上游水位壅高和下游回流区最大宽度的理论关系式, 并用室内实验结果进行了验证. 研究表明, 水位壅高和最大回流宽度取决于弗罗德数和折弯角. 还提出了计算水位壅高和最大回流宽度的显式关系式.

关键词: 急弯, 水位壅高, 回流区