Drag force parameters of rigid and flexible vegetal elements

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

This paper compares parameters that characterize vegetation flexibility effects on flow resistance and drag. Drag forces have been measured in a flume for simple cylindrical obstructions of the same shape and size but with different flexibility under several flow conditions. This data set is used to fit drag parameters and to relate their value to flexibility through the Cauchy Number. A formulation is presented where the drag coefficient is evaluated as a function of a new calibration velocity parameter which is related to the elastic modulus of the obstruction. While the use of a Vogel exponent and reference velocity provides a similar response, the reference velocity when used is somewhat nebulous and appears to have a critical impact on the parameter and the drag force calculated. The proposed formulation for drag reduction is more consistently estimated for the range of flexibilities in this study.

Original languageEnglish (US)
Pages (from-to)3292-3302
Number of pages11
JournalWater Resources Research
Volume51
Issue number5
DOIs
StatePublished - May 1 2015

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drag
drag coefficient
elastic modulus
parameter
calibration
vegetation

Keywords

  • Cauchy Number
  • drag forces
  • elastic modulus
  • flexibility
  • vegetated flow

Cite this

Drag force parameters of rigid and flexible vegetal elements. / Chapman, John A; Wilson, Bruce N; Gulliver, John S.

In: Water Resources Research, Vol. 51, No. 5, 01.05.2015, p. 3292-3302.

Research output: Contribution to journalArticle

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