School of Physics Lecture Demonstration Manual

Fc-2 The Venturi Flow Meter

Published: Monday 13 March 2006 - Updated: Tuesday 29 March 2011


To Demonstrate how Bernoulli's law applies to pressure


Venturi tube


Click on pictures to enlarge.

Venturi Pic

Venturi Diagram


The Venturi Flow Meter


The Venturi Flowmeter has a U tube manometer connected across two points of varying cross section. For horizontal fluid flow Bernoulli's equation states that the pressure is reduced where the cross ectional area is narrower. The pressure difference between these points is readily seen with even a modest flow of water. If required a Camera can be trained on the unit for a close up.

Safety notes

Sharps Safety 


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