Venturi Meter Flow Rate
Venturi Meter Flow Rate
A venturi infers flow from the pressure drop as the fluid speeds up through its throat — a low-loss flow meter.
The flow is Q = C_d·A·√(2·Δp/ρ). where C_d is the discharge coefficient, A the throat area, Δp the pressure drop and ρ the density.
Inputs
C_d := 0.97=0.97
A := 0.002 m^2=2e-03 m^2
dP := 8000 Pa=8000 Pa
rho := 1000 kg/m^3=1000 kg/m^3
Apply the venturi discharge equation.
Q := C_d·A·sqrt(2·dP/rho)=7.76e-03 m^3/s
Results
The venturi recovers most of its pressure downstream, so it loses far less energy than an orifice plate for the same measurement.
Assumptions & limitations
- Incompressible, steady flow.
- Discharge coefficient near 1.
- Throat area used.