# Venturi Meter Flow Rate

Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

Venturi meter flow rate measures the velocity of a fluid through a pipe.

Bernoulli's Equation

## Venturi Meter Flow Rate Formula

 $$\large{ Q = A_2 \sqrt { \frac { {2 \; \left ( p_1 \; - \; p_2 \right)} } { \rho \; \left( 1\; - \; \left( \frac {A_2} {A_1} \right) ^2 \right) } } }$$

### Where:

 Units English Metric $$\large{ Q }$$ = flow rate $$\large{\frac{ft^3}{sec}}$$ $$\large{\frac{m^3}{s}}$$ $$\large{ A_1 }$$ = area 1 $$\large{in^2}$$ $$\large{mm^2}$$ $$\large{ A_2 }$$ = area 2 $$\large{in^2}$$ $$\large{mm^2}$$ $$\large{ p_1 }$$ = pressure 1 $$\large{\frac{lbf}{in^2}}$$ $$\large{Pa}$$ $$\large{ p_2 }$$ = pressure 2 $$\large{\frac{lbf}{in^2}}$$ $$\large{Pa}$$ $$\large{ \rho }$$ = density of the fluid $$\large{\frac{lbm}{ft^3}}$$ $$\large{\frac{kg}{m^3}}$$

Tags: Flow Equations