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.
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)