Flow Characteristics of Rectangular Broad-Crested Weirs with Sloped Upstream Face

Ehsan GOodarzi; Javad Farhoudi; Naser Shokri

doi:10.2478/v10098-012-0008-1

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Flow Characteristics of Rectangular Broad-Crested Weirs with Sloped Upstream Face

Journal of Hydrology and Hydromechanics

Volume 60 (2012): Issue 2 (June 2012)

By: Ehsan GOodarzi, Javad Farhoudi and Naser Shokri

Open Access

|Jun 2012

Abstract

The hydraulc characteristics of flow over rectangular broad-crested weirs with varying upstream slopes were experimentally studied. A series of laboratory experiments was performed to investigate the effects of changing upstream slopes from 90° to 75°, 60°, 45°, 30°, 22.5°, 15°, and 10° on the flow surface pattern, discharge coefficient values, approach velocity profile and flow separation zone. In addition, a new mathematical relationship for water surface profile and a new correction factor to estimate discharge coefficient over weirs with various upstream slopes were introduced. The results showed decreasing upstream slopes from 90° to 10° leading to increasing discharge coefficient values and dissipation of the separation zone.

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Articles in this issue

DOI: https://doi.org/10.2478/v10098-012-0008-1 | Journal eISSN: 1338-4333 | Journal ISSN: 0042-790X

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Language: English

Page range: 87 - 100

Published on: Jun 14, 2012

Published by: Slovak Academy of Sciences, Institute of Hydrology

In partnership with: Paradigm Publishing Services

Publication frequency: 4 issues per year

Keywords:

Broad Crested Weir,

Upstream Face Slope,

Flow Surface Pattern,

Discharge Coefficient,

Related subjects:

Introductions and overviews,

Engineering, other

© 2012 Ehsan GOodarzi, Javad Farhoudi, Naser Shokri, published by Slovak Academy of Sciences, Institute of Hydrology
This work is licensed under the Creative Commons License.

Volume 60 (2012): Issue 2 (June 2012)