 # V notch Weir Calculator A V notch weir is a type of flow gauge. V notch weir is used to measure the flowing rate of water in a V shaped or triangular shaped. The purpose of v notch weir is to ensure that the velocity flowing over the weir is only dependent on the upstream head. The low rate of water by V notch weir is denoted by the symbol "q".

V-Notch Weir Discharge Calculation

θ ("Angle in Radian = between0.349 - 1.75 )
h
Cd
m3/s

Formula

q = 8/15 ×Cd/ ×(2g)1/2 ×tan(θ/2) ×h3/2

Where,
q = Flow Rate
Cd = Discharge Constant
θ = V - Notch Angle
g = gravity (9.81 m/s²)
h = Head on the Weir

This advanced online V notch Weir Calculator is used to calculate the flow rate of water in V shaped or triangular shaped weir.

Example:
Calculate the Flow rate in V-notch weir for the given details.
V - Notch angle (θ) = 25 degree
Head on the Weir (h) = 20
Discharge Constant (Cd) = 15

Solution:
Apply Formula:
q = 8/15 ×Cd × (2g)1/2 × tan(θ/2) ×h3/2
q = 8/15*15*(2*9.81)*tan(25/2)*20 3/2
Flow Rate (q) = 702.6510823885201 m3