连续微弯弯道水力特性试验及模拟研究

Hydraulic Characteristics of Continuous Micro-bend Channel:Flume Experiment and Numerical Simulation

为了研究河流的连续微弯弯道水力特性,通过建立曲折系数为1.07的连续弯道模型进行试验,并利用Reynolds应力模型进行模拟计算,从水面线、流速场、弯道环流及强度等方面研究了小曲折系数连续弯道水力特性。结果表明:Reynolds应力模型能够较好地模拟连续弯道水流;在同一断面,近凸岸的纵向流速垂线分布接近对数流速分布,近凹岸的纵向流速垂线分布呈随相对水深增大而先增大后减小的规律,呈现"凸肚"形;在弯道环流方面,呈现非对称的双环流结构;水面和槽底处的环流强度大于水体中部,凹岸的环流强度大于凸岸的环流强度。成果为研究小曲折系数弯道的河流水力特性提供了借鉴与参考。

The hydraulic characteristic of continuous micro-bend channel was researched on a continuous bend physical model with sinuosity of 1.07 and Reynolds stress model.The water line,flow velocity field,circulating flow in bend channels,and intensity were examined.Reynolds stress model is proved well simulates the flow in continuous bend.In a given section,the vertical longitudinal velocity distribution in the adjacent of convex bank approached to logarithmic distribution,while the vertical longitudinal velocity adjoining concave bank displayed a bulging shape,increasing firstly and then decreasing with the growth of relative water depth.Circulating flow in bends displayed asymmetric double circulation structure,with the flow intensity larger in the surface and bottom of flume than that in the central part,and larger at concave bank than that at convex bank.