Numerical evaluation of turbulent flow in a circular conduit along a side weir
Numerical evaluation of turbulent flow in a circular conduit along a side weir
复制标题
沿侧堰的圆形管道内湍流的数值计算
DOI：
10.1007/s13201-019-1117-3
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发表时间：
2019
影响因子：
5.5
通讯作者：
S. Shabanlou
中科院分区：
文献类型：
--
作者：
Meysam Bagherifar;Ayoub Emdadi;H. Azimi;Babak Sanahmadi;S. Shabanlou
侧堰用作主河道侧壁上的槽，用于引导超过堰顶的多余水。这种结构用于灌溉、排水网络和城市污水处理系统的水位控制。此外，圆形通道非常重要，因为相当长的污水处理和输送管道系统是由圆形通道组成的。本文模拟了沿侧堰流过圆形沟道的入流自由面、湍流度和流场的变化。这意味着对于流动自由面和流场湍流的变化，分别使用了流体体积格式和RNG k -ε湍流模型。为了验证数值模型的准确性，研究了沿侧堰流动自由面变化情况，并将侧堰流量系数、侧堰流量、侧堰上游弗劳德数和比能与实验测量值进行了比较。仿真结果与实验结果的对比表明，CFD模型具有较高的精度。换句话说，得到的流动自由表面的均方根误差百分比为0.554%，平均绝对误差为0.547%。计算得到侧堰上下游比能平均差约2.1%。模拟的主要目的是了解亚临界流态下带侧堰的圆形通道的流动行为。
Side weir is used as a slot in the side wall of the main channel to direct excess water that is above the weir crest. Such structures are used in control of flow level in irrigation, drainage networks and urban sewage disposal systems. Furthermore, circular channels are pretty important because considerable length of sewage disposal and transmission pipeline system is made of circular channels. In this study, changes inflow free surface, turbulence and flow field passing through a circular channel along a side weir are simulated. This means that for modeling the variations in flow free surface and the flow field turbulence, the volume-of-fluid scheme and RNG k–ε turbulence model are used, respectively. In order to validate the accuracy of the numerical model, the flow free surface changes along the side weir, the discharge coefficient of side weir, discharge of side weir, Froude number at upstream of the side weir and specific energy are compared with the experimental measurements. Comparison of simulation results with the experimental measurements shows high accuracy of CFD model. In other words, the root-mean-square error percent and the mean absolute error for flow free surface are, respectively, obtained to be 0.554% and 0.547%. Moreover, average difference between the specific energy at upstream and downstream of the side weir is calculated about 2.1%. The main purpose of this simulation is gaining an understanding of behavior of the passing flow through circular channels with side weir for subcritical flow regime.