TECHNICAL NOTE: THEORETICAL APPROACH TO STAGE-DISCHARGE RELATIONSHIP FOR A CIRCULAR SHARP-CRESTED WEIR

L. AMARA, B. ACHOUR

Abstract


A novel theoretical approach for the flow discharge relationship in a circular sharp crested weir is developed in the present paper. Based on the application of the energy equation applied between a section taken in the approach channel and the weir under critical flow conditions, a general stage-discharge relationship is obtained taking into account width contraction effect and kinetic energy in the approaching channel. A correction function is introduced considering the simplifying assumptions assumed in the theory which neglected both the effects of viscosity, the curvature of the streamlines due to the contraction of the weir and surface tension.

Derivation of the discharge coefficient expression for classical stage-discharge equation is also given. In order to check the proposed model, verification with laboratory measurement data available in literature are made. Results show a very good agreement between predicted and actual discharge.

Keywords


Circular weir, Stage-discharge relationship, Discharge coefficient, Approach velocity.

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References


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