Question

What is the principle of venturimeter? Derive an expression for the rate of flow of liquid through it.

Solution

Venturimeter is based on Bernoulli's theorem. It consists of a two truncated tubes connected by a pipe at narrow ends. The pipe connecting the two tubes is called throat.

i) Venturimeter tube is positioned horizontally and the liquid is made to enter in it from end A and after passing through throat BC, it leaves tube at end D.

ii) Let at A,
Area of cross-section of tube = a₁,
Pressure of liquid = P₁
Velocity = v₁
At the throat,
Area of cross-section of tube = a₂
Pressure of liquid = P₂
Velocity be v₂According to the equation of continuity,
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Mechanical Properties Of Fluids

What is the principle of venturimeter? Derive an expression for the rate of flow of liquid through it.

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