2.1. Principle of Venturimeter: Venturimeter working is based on the Bernoulli’s principle. As the velocity increases the pressure decreases due to the difference in the cross-sectional area of the inlet and the throat. The cross-sectional are of the inlet is larger as compare to the throat thus the flow rate at the throat will be larger as compare to the inlet. Thus larger flow rate at the throat will result in decrease in pressure at this point. This happens According to the continuity equation. The difference in the pressure between the inlet and the throat is measured by means of a manometer attached externally to the pressure points. Venturi Effect When a fluid is flowing through a pipe and it faces constriction, the velocity of the flow increases with the constriction with a corresponding drop in static pressure. This is called the Venture effect. According to Bernoulli’s principle the flow speed is inversely proportional to its static pressure. Which in terms means that when the velocity of the flowing fluid increases the pressure decreases. (ScienceStruck, 2018,Venturi effect. Fig 1.2: Venturi Effect.
