Entropic approach to estimate the mean flow velocity:experimental investigation in laboratory flumes

Donatella Termini, Tommaso Moramarco

Risultato della ricerca: Article

6 Citazioni (Scopus)

Abstract

The paper deals with the linear entropic relationship between the maximum velocity, u max , and the mean flow velocity, u m, through a dimensionless parameter U (M), in open-channel flow. The analysis is conducted with the aid of experimental data collected in straight laboratory flumes under different bed and side-walls roughness conditions. In particular, rough/vegetated beds and smooth/rough side-walls conditions have been investigated. The results show that, in the investigated conditions (with exception of low- submergence vegetated bed— h/k v \2), U (M) can be assumed equal to a value that is very close to that found in natural channels. This demonstrates that U (M) is able to implicitly reflect the different hydraulic behavior which is determined in rough and submerged vegetated beds. Thus, the entropy-based Manning’s roughness formula has been validated and the sensitivity analysis of Manning’s coefficient with the values of y o (location of the zero-velocity plane) has been also performed. It is found that this formula is quite robust to represent the observed flow resistance also in the presence of vegetation.
Lingua originaleEnglish
pagine (da-a)1163-1179
Numero di pagine17
RivistaEnvironmental Fluid Mechanics
Volume15
Stato di pubblicazionePublished - 2015

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Flow velocity
flow velocity
roughness
Surface roughness
Open channel flow
open channel flow
submergence
Sensitivity analysis
entropy
sensitivity analysis
Entropy
Hydraulics
hydraulics
vegetation
laboratory
analysis
parameter

All Science Journal Classification (ASJC) codes

  • Environmental Chemistry
  • Water Science and Technology

Cita questo

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title = "Entropic approach to estimate the mean flow velocity:experimental investigation in laboratory flumes",
abstract = "The paper deals with the linear entropic relationship between the maximum velocity, u max , and the mean flow velocity, u m, through a dimensionless parameter U (M), in open-channel flow. The analysis is conducted with the aid of experimental data collected in straight laboratory flumes under different bed and side-walls roughness conditions. In particular, rough/vegetated beds and smooth/rough side-walls conditions have been investigated. The results show that, in the investigated conditions (with exception of low- submergence vegetated bed— h/k v \2), U (M) can be assumed equal to a value that is very close to that found in natural channels. This demonstrates that U (M) is able to implicitly reflect the different hydraulic behavior which is determined in rough and submerged vegetated beds. Thus, the entropy-based Manning’s roughness formula has been validated and the sensitivity analysis of Manning’s coefficient with the values of y o (location of the zero-velocity plane) has been also performed. It is found that this formula is quite robust to represent the observed flow resistance also in the presence of vegetation.",
author = "Donatella Termini and Tommaso Moramarco",
year = "2015",
language = "English",
volume = "15",
pages = "1163--1179",
journal = "Environmental Fluid Mechanics",
issn = "1567-7419",
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T1 - Entropic approach to estimate the mean flow velocity:experimental investigation in laboratory flumes

AU - Termini, Donatella

AU - Moramarco, Tommaso

PY - 2015

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N2 - The paper deals with the linear entropic relationship between the maximum velocity, u max , and the mean flow velocity, u m, through a dimensionless parameter U (M), in open-channel flow. The analysis is conducted with the aid of experimental data collected in straight laboratory flumes under different bed and side-walls roughness conditions. In particular, rough/vegetated beds and smooth/rough side-walls conditions have been investigated. The results show that, in the investigated conditions (with exception of low- submergence vegetated bed— h/k v \2), U (M) can be assumed equal to a value that is very close to that found in natural channels. This demonstrates that U (M) is able to implicitly reflect the different hydraulic behavior which is determined in rough and submerged vegetated beds. Thus, the entropy-based Manning’s roughness formula has been validated and the sensitivity analysis of Manning’s coefficient with the values of y o (location of the zero-velocity plane) has been also performed. It is found that this formula is quite robust to represent the observed flow resistance also in the presence of vegetation.

AB - The paper deals with the linear entropic relationship between the maximum velocity, u max , and the mean flow velocity, u m, through a dimensionless parameter U (M), in open-channel flow. The analysis is conducted with the aid of experimental data collected in straight laboratory flumes under different bed and side-walls roughness conditions. In particular, rough/vegetated beds and smooth/rough side-walls conditions have been investigated. The results show that, in the investigated conditions (with exception of low- submergence vegetated bed— h/k v \2), U (M) can be assumed equal to a value that is very close to that found in natural channels. This demonstrates that U (M) is able to implicitly reflect the different hydraulic behavior which is determined in rough and submerged vegetated beds. Thus, the entropy-based Manning’s roughness formula has been validated and the sensitivity analysis of Manning’s coefficient with the values of y o (location of the zero-velocity plane) has been also performed. It is found that this formula is quite robust to represent the observed flow resistance also in the presence of vegetation.

UR - http://hdl.handle.net/10447/148847

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SP - 1163

EP - 1179

JO - Environmental Fluid Mechanics

JF - Environmental Fluid Mechanics

SN - 1567-7419

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