Study on Velocity Distribution of Flow With Submerged Flexible Vegetations Based on Mixing-Length Approach

HUAI Wen-xin; HAN Jie; ZENG Yu-hong; AN Xiang; QIAN Zhong-dong

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Article Navigation > Applied Mathematics and Mechanics > 2009 > 30(3): 325-332

HUAI Wen-xin, HAN Jie, ZENG Yu-hong, AN Xiang, QIAN Zhong-dong. Study on Velocity Distribution of Flow With Submerged Flexible Vegetations Based on Mixing-Length Approach[J]. Applied Mathematics and Mechanics, 2009, 30(3): 325-332.

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Study on Velocity Distribution of Flow With Submerged Flexible Vegetations Based on Mixing-Length Approach

State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, P. R. China

Received Date: 2008-09-03
Rev Recd Date: 2008-11-21
Publish Date: 2009-03-15

Abstract

Abstract

Choosing PVC slice to simulate the flexible vegetation, the laboratory experiments were carried out in an open channel with submerged flexible vegetation, and 3D acoustic Doppler velocimeter (Micro ADV) was introduced to measure the local flow velocities and Reynolds stress. The result showed that the hydraulic characteristics in the non-vegetation layer and the vegetation layer are totally different. In the region above the vegetation, Reynolds stress's distribution is linear; meanwhile, measured velocity's profile is a classical logarithmic one. Based on the concept of nwe/riverbed0, the river compress parameter which represented the impact of vegetation on river was given for the first time and a new mixing length expression was assumed with reason. The formula of time-averaged velocity deduced from the mixing length expression had advantages of less parameters needed, simple calculation and useful application.
- flexible vegetation,
- PVC slice,
- Micro ADV,
- mixing-length approach,
- stream-wise velocity distribution,
- Reynolds stress,
- river compressed parameter

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References(25)

References

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