I have forgotten

• https://me.yahoo.com

# Triangular Notch

Discharge over a Triangular Notch
View version details

### Key Facts

Gyroscopic Couple: The rate of change of angular momentum () = (In the limit).
• = Moment of Inertia.
• = Angular velocity
• = Angular velocity of precession.

Blaise Pascal (1623-1662) was a French mathematician, physicist, inventor, writer and Catholic philosopher.

Leonhard Euler (1707-1783) was a pioneering Swiss mathematician and physicist.

## Overview

A triangular notch is also called a V-notch. Consider a triangular notch, in one side of the tank, over which water is flowing as shown in figure.

Let,
• H = Height of the liquid above the apex of the notch
• θ = Angle of the notch
• Cd = Coefficient of discharge

From the geometry of the figure, we find that the width of the notch at the water surface,

Area of the strip =

We know that the theoretical velocity of water through the strip =

and discharge over the notch,

The total discharge over the whole notch may be found out only by integrating the above equation within the limits 0 and H.

A triangular notch gives more accurate results for low discharges than rectangular notch and the same triangular notch can measure a wide range of flows accurately.

Example:
[metric]
##### Example - Discharge through a triangular notch
Problem
A right-angled V-notch was used to measure the discharge of a centrifugal pump. If the depth of water at V-notch is 200mm, calculate the discharge over the notch in liters per minute. Assume coefficient of discharge as 0.62.
Workings
Given,
• 
• 
• 

We know that the discharge over the triangular notch,







Solution
Discharge over the notch = 1560 liters/s