挑坎体型对水舌形态和下游河床冲刷至关重要, 基于水工模型试验, 利用正交试验设计对纳子峡工程泄洪洞 扭曲鼻坎体型进行优化研究。采用极差分析和方差分析, 选取最大冲坑深度、冲刷最低点到边坡的距离、左侧挑距、 右侧挑距和水舌宽度作为评价指标对扭曲鼻坎左侧边墙向右偏移距离、右侧边墙向右偏移距离、鼻坎扭曲程度系数 3 个因素进行计算, 分析各因素对评价指标的敏感性, 以确立扭曲鼻坎的最优体型。结果表明, 各水力学特性指标 对左侧边墙向右岸的偏移量的变化更敏感, 其余因素对扭曲挑坎的消能效果影响较小, 通过正交设计分析所得的最 优体型, 其水力特性指标均明显优于其他方案, 所得成果可为实际工程扭曲鼻坎体型的设计提供依据。

The shape of a flip bucket is ver y important fo r the shape o f the w ater tong ue and the sco uring of the downstream ri2 v erbed. Based o n the hydraulic model test , optim izing the shape of the skew bucket of the Nazix ia spillw ay tunnel by o rthog onal desig n. Using ex tr eme difference analy sis and va riance analy sis, the max imum crater depth, t he dist ance from the low est point to the slope, the left jet tr ajecto ry leng th, the right jet t rajecto ry leng th and nappe width wer e selected as the ev aluation indicators for t he o ffset o f the left and rig ht side w alls o f the skew bucket. The three factors of the deg ree o f distortion o f the no se wer e calculated, and the sensitiv ity o f each facto r to the evaluatio n index w as analy zed t o establish the optimal flip bucket fo rm of the skew bucket. The r esults show ed t hat the hydraulic characteristics w ere more sensitive t o t he change of the offset of the left side wall to the rig ht bank. T he ot her facto rs had little effect on t he energ y dissipation effect of the skew bucket. The optimal shape was also analyzed by orthogo na l desig n. The hy dr aulic char acteristics w er e superio r to ot her schemes, while t he obtained r esults co uld pr ovide a basis for the design of t he actual engineering skew bucket.

国家自然科学基金( 51579172) ; 高等学校学科创新引智计划( B14012)