scholarly journals Non-Newtonian Open Channel Flow — A Simple Method of Estimation of Laminar/Turbulent Transition and Flow Resistance

2008 ◽  
Author(s):  
Timothy Fitton
Keyword(s):  
Channel Flow ◽  
Flow Resistance ◽  
Open Channel ◽  
Open Channel Flow ◽  
Simple Method ◽  
Turbulent Transition ◽  
Laminar Turbulent Transition

scholarly journals Use of conventional flow resistance equations and a model for the Nikuradse roughness in vegetated flows at high submergence

2018 ◽  
Vol 66 (1) ◽  
pp. 107-120 ◽  
Author(s):  
Paola Gualtieri ◽  
Sergio De Felice ◽  
Vittorio Pasquino ◽  
Guelfo Pulci Doria
Keyword(s):  
Experimental Data ◽  
Channel Flow ◽  
Flow Resistance ◽  
Open Channel ◽  
Open Channel Flow ◽  
Experimental Methodology ◽  
Flow Depth ◽  
Vegetation Height ◽  
Rigid Vegetation ◽  
Grain Roughness

Abstract This study examines the problem of flow resistance due to rigid vegetation in open channel flow. The reliability of the conventional flow resistance equations (i.e. Keulegan, Manning and Chézy-Bazin) for vegetated flows at high submergence, i.e. h/k >5, (where h = flow depth and k = vegetation height) is assessed. Several modern flow resistance equations based on a two-layer approach are examined, showing that they transform into the conventional equations at high submergences. To compare the conventional flow resistance equations at high submergences, an experimental methodology is proposed and applied to the experimental data reported in the literature and collected for this study. The results demonstrate the reliability of the Keulegan equation in predicting the flow resistance. Based on the obtained results, a model to evaluate the Nikuradse equivalent sand-grain roughness, kN, starting from the vegetation height and density, is proposed and tested.

Sign in / Sign up

Export Citation Format

Share Document