| 刘春晶,李丹勋,王兴奎.明渠均匀流的摩阻流速及流速分布[J].水利学报,2005,36(8):0950-0955 |
| 明渠均匀流的摩阻流速及流速分布 |
| Experimental study on friction velocity and velocity profile of open channel flow |
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| DOI： |
| 中文关键词: 明渠流 流速分布 摩阻流速 试验研究 |
| 英文关键词: open channel flow velocity distribution friction velocity experimental study |
| 基金项目: |
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| 摘要点击次数: 4055 |
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| 中文摘要: |
| 在水槽系统上对明渠恒定均匀流进行了系列实验，利用实测流速资料，对明渠均匀流摩阻流速的各种方法(雷诺应力法、对数流速分布法、阻力平衡法等)的计算结果进行了对比，并分析了流速分布。结果表明：(1)利用阻力平衡法计算摩阻流速时应考虑边壁影响；(2)包含尾流函数的对数-尾流公式比单一对数公式可以更好的符合实测数据。用单一对数公式描述垂线流速分布时，应采用较小的Karman常数；(3)现有大量明渠均匀流实测资料中，用常用的Karman常数(κ=0.4)时单一对数公式仍可以较好的表示全水深流速分布是因为采用了较大的摩阻流速。 |
| 英文摘要: |
| A series of experiments on steady uniform flow in open channel were conducted in a flume. Vertical distributions of flow velocity were measured by using 2-D laser velocimetry. The friction velocities were calculated by three methods based on the experimental data. It is found that:1.the effect of sidewall should be considered when using global resistance method to estimate the friction velocity;2.the log-wake law for describing the velocity profile of open channel flow is better than the logarithmic law and a smaller von Karman constant should be considered when log-law is used to depict the velocity distribution;3.since larger friction velocities are adopted the log-law with adopting a usual von Karman constant(κ=0.4)can be used to express the velocity profile of steady uniform open channel flow. |
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