Variation of Roughness Coefficients for Unsubmerged and Submerged Vegetation

  title={Variation of Roughness Coefficients for Unsubmerged and Submerged Vegetation},
  author={Fu‐Chun Wu and Hsieh Wen Shen and Yi‐Ju Chou},
  journal={Journal of Hydraulic Engineering},
This paper investigates the variation of the vegetative roughness coefficient with the depth of flow. A horsehair mattress is used in the experimental study to simulate the vegetation on the watercourses. Test results reveal that the roughness coefficient reduces with increasing depth under the unsubmerged condition. However, when fully submerged, the vegetative roughness coefficient tends to increase at low depths but then decrease to an asymptotic constant as the water level continues to rise… 

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