Pitot Tube Velocity
Pitot Tube Velocity
A Pitot tube reads the difference between stagnation and static pressure, from which Bernoulli gives the speed — how aircraft measure airspeed.
The velocity is v = √(2·Δp/ρ). where Δp is the dynamic pressure and ρ the fluid density.
Inputs
dP := 1500 Pa=1500 Pa
rho := 1.225 kg/m^3=1.23 kg/m^3
Invert the dynamic-pressure relation for velocity.
v := sqrt(2·dP/rho)=49.49 m/s
Results
The dynamic pressure grows with the square of speed, so the velocity follows the square root of the reading. Air density (altitude) must be corrected for true airspeed.
Assumptions & limitations
- Incompressible flow (low Mach).
- Aligned with the flow.
- Ideal pressure recovery.