| 摘要: |
| 为减轻渡槽在大流量运行时，出现的水位波动较大、紊流、涡流等复杂流态，选取典型双孔渡槽模型进行水力学模型实验和三维数值模拟，应用物理模型与数值模拟相结合的方法研究渡槽出口的卡门涡街在被边界约束时对其上游产生的波浪回涌现象，通过对其机理的研究提出“纺锤型”导流墩方案。研究发现卡门涡街脱落频率与上游回涌波浪频率一致，边界约束下卡门涡街对上游流态影响机理为：涡街交替脱落产生横向的交变作用力，在边界约束下局部阻水进而形成波动向上游传递，随着涡街的交替脱落，上游形成波浪交替回涌现象。施加“纺锤型”导流墩后，进出口流态得到改善，能够大幅减轻涡街强度和对上游流态的影响，槽身最大波幅消减度达到80%以上。对不同长度导流墩组合进行对比试验后，提出进、出口导流墩纵横比AR=L/W分别为1.5、2.0的最佳性价比组合。 |
| 关键词: 卡门涡街 典型双孔渡槽 数值模拟 导流墩 |
| DOI： |
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| 基金项目:国家自然科学重点项目(项目编号41930643) |
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| Study on improvement scheme of complex flow pattern in typical double-hole aqueduct |
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xuehai1, liupei1, WANG Pengtao2, PAN Conghui2, CHI Yinghua2
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1.School of Water Conservancy, North China University of Water Resources and Electric Power;2.North China University of Water Resources and Electric Power
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| Abstract: |
| In order to reduce the complex flow patterns such as large water level fluctuation, turbulence and eddy current when the aqueduct is running with large flow, a typical double-hole aqueduct model is selected for hydraulic model experiment and three-dimensional numerical simulation. the wave surge phenomenon caused by the Carmen vortex street at the outlet of the aqueduct when it is constrained by the boundary is studied by the method of physical model and numerical simulation, and the scheme of "spindle type" diversion pier is put forward through the study of its mechanism. It is found that the shedding frequency of Carmen vortex street is consistent with the upstream surge wave frequency, and the influence mechanism of Carmen vortex street on upstream flow pattern under boundary constraint is as follows: the alternating shedding of Carmen vortex street produces transverse alternating force. Under the boundary constraint, the local blocking water forms the wave transfer to the upstream, and with the alternating shedding of the vortex street, the upstream wave alternately returns. After applying the "spindle type" diversion pier, the inlet and outlet flow pattern is improved, which can greatly reduce the vortex street strength and the influence on the upstream flow pattern, and the maximum amplitude reduction of the trough body is more than 80%. After the comparative test of the combination of diversion piers of different lengths, the best performance-to-price ratio combination of inlet and outlet diversion piers with aspect ratio AR=L/W of 1.5,2.0 is put forward. |
| Key words: typical double-hole aqueduct numerical simulation vortex street diversion facilitie |
