Numerical study of flow pattern around lateral intake in a curved channel
Numerical study of flow pattern around lateral intake in a curved channel
复制标题
DOI：
10.1142/s0129183119500839
复制
发表时间：
2019-11
影响因子：
1.9
通讯作者：
H. Montaseri;H. Asiaei;A. Baghlani;P. Omidvar
中科院分区：
文献类型：
--
作者：
H. Montaseri;H. Asiaei;A. Baghlani;P. Omidvar
本文采用三维数值模型SSIM2. 0对有侧向进水口的渠道弯曲流场进行了数值研究。研究了弯曲对进水口周围流场结构的影响，并与试验结果进行了比较。试验是在一个带有侧向进气口的U形弯曲中进行的。进水口位于180 °弯曲外侧115 °处，导流角45 °，试验数据可用于数值模型的标定和验证。结果表明，试验中既观察到了中心区的横流环流，也观察到了外侧区的横流环流，而由于湍流模型的局限性，数值模型只捕捉到了中心区的横流环流。在进水口后的弯道中，实验和数值模拟结果均显示了另一种类型的双胞环流，即顺时针的中心区环流和逆时针的内堤和自由面附近的环流（内堤环流）。研究表明，数值模型能很好地模拟出明渠及进水口附近的流线、速度场和流态。对弯道侧向取水口水流流态的研究表明，与直槽分流情况相反，弯道侧向取水口近水面处的分流面宽度大于近床面处的分流面宽度。最后，研究了侧向进水口位置、导流角、流量比和上游佛汝德数对水流流态的影响。
This paper deals with numerical study of flow field in a channel bend in presence of a lateral intake using three-dimensional numerical model SSIIM2. The effects of bend on the structure of the flow around the intake are investigated and compared with the experimental data. The tests are carried out in a U-shaped channel bend with a lateral intake. The intake is located at the outer bank of an 180∘ bend at position 115∘ with 45∘ diversion angle and the experimental data can be used to calibrate and validate numerical models. The results show that both the center-region and outer-bank cross-stream circulations are observed in the experiments while only the former is captured by the numerical model due to the limitations of the turbulence model. In the curved channel after the intake, both experimental and numerical results show another type of bi-cellular circulations in which clockwise center-region circulations and counterclockwise circulations near the inner bank and the free surface (inner-bank circulations) are captured. The study shows that the numerical model very satisfactorily predicts streamlines, velocity field and flow pattern in the channel and in vicinity of the intake. Investigation of flow pattern around lateral intake in channel bends shows that contrary to the case of flow diversion in straight channels, the width of the dividing stream surface near water surface level is greater than that of near bed level. Finally, the effects of position and diversion angle of the lateral intake, discharge ratio and upstream Froude number on the flow pattern are investigated.