scholarly journals Reply to Comment by J. Qin and T. Wu on “Analysis of Flow Resistance Equations in Gravel Bed Rivers With Intermittent Regimes: Calabrian fiumare Data Set”

2020 ◽  
Vol 56 (3) ◽  
Author(s):  
G. Mendicino ◽  
F. Colosimo
Keyword(s):  
Flow Resistance ◽  
Data Set ◽  
Gravel Bed ◽  
Gravel Bed Rivers

Temporal variations in bedload transport rates and sediment storage in gravel-bed rivers

1992 ◽  
Vol 16 (3) ◽  
pp. 319-338 ◽  
Author(s):  
Trevor Hoey
Keyword(s):  
Three Dimensional ◽  
Temporal Variations ◽  
Sampling Interval ◽  
Bedload Transport ◽  
Sediment Storage ◽  
Data Set ◽  
Gravel Bed ◽  
Wide Range ◽  
Gravel Bed Rivers ◽  
Bed Waves

Temporal variability in bedload transport rates and spatial variability in sediment storage have been reported with increasing frequency in recent years. A spatial and temporal classification for these features is suggested based on the gravel bedform classification of Church and Jones (1982). The identified scales, meso-, macro-, and mega- are each broad, and within each there is a wide range of processes acting to produce bedload fluctuations. Sampling the same data set with different sampling intervals yields a near linear relationship between sampling interval and pulse period. A range of modelling strategies has been applied to bed waves. The most successful have been those which allow for the three-dimensional nature of sediment storage processes, and which allow changes in the width and depth of stored sediment. The existence of bed waves makes equilibrium in gravel-bed rivers necessarily dynamic. Bedload pulses and bed waves can be regarded as equilibrium forms at sufficiently long timescales.

Flow Resistance in Gravel-Bed Rivers

1979 ◽  
Vol 105 (4) ◽  
pp. 365-379 ◽  
Author(s):  
Richard D. Hey
Keyword(s):  
Flow Resistance ◽  
Gravel Bed ◽  
Gravel Bed Rivers

scholarly journals Assessing theoretical flow velocity profile and resistance in gravel bed rivers by field measurements

2018 ◽  
Vol 49 (4) ◽  
pp. 220-227 ◽  
Author(s):  
Vito Ferro ◽  
Paolo Porto
Keyword(s):  
Velocity Profile ◽  
Flow Velocity ◽  
Froude Number ◽  
Flow Resistance ◽  
Field Measurements ◽  
Mean Flow ◽  
Gravel Bed ◽  
Wide Range ◽  
Gravel Bed Rivers ◽  
Resistance Equation

Previous studies showed that integrating a power velocity profile, deduced applying dimensional analysis and the incomplete self-similarity condition, the flow resistance equation for open channel flow can be obtained. At first, in this paper the relationship between the Γ function of the power velocity profile, the channel slope and the Froude number, which was already empirically introduced in a previous paper, is now theoretically deduced. Then this relationship is calibrated using the field measurements of flow velocity, water depth and bed slope carried out in 101 reaches of gravel bed rivers available by literature. The proposed relationship for estimating Γ function and the theoretical flow resistance equation are also tested by an independent dataset of 104 reaches of some gravel bed rivers (Fiumare) in Calabria region. Finally, the theoretically-based relationship for estimating the Γ function is calibrated by the overall available database (205 reaches). In this way the three coefficients of the theoretically based Γ function are estimated for a wide range of slopes (0.1%-6.19%) and hydraulic conditions (Froude number values ranging from 0.08 to 1.25). In conclusion, the analysis shows that the Darcy-Weisbach friction factor for gravel bed rivers can be accurately estimated by the approach based on a power-velocity profile and the theoretically-based relationship proposed for estimating Γ function. The analysis also points out a performance in estimating mean flow velocity better than that obtained in a previous study carried out by the authors.

Sign in / Sign up

Export Citation Format

Share Document