Open Channel Flow: Rectangular Notch

The minimum width of Notches shall be at least 150 mm. Rectangular notches are generally used for measuring small flows.

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Discharge Calculation in Open Channels



The discharge calculation formula from Rectangular notches is as given below;



Q = Discharge in cubic meter per second,

be = Effective Width in meters,

h = Effective Head in meters,

Ce = Coefficient of Effective Discharge

(The value of Ce varies from 0.58 to 0.7 for values of b/B varying from 0.0 to 0.8, where B is Width of Cahnnel)