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Pitot tube
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Measures flow speed from stagnation pressure.
Measures flow speed from the difference between stagnation pressure (fluid stopped) and static pressure: v = √(2ΔP/ρ). Used on aeroplanes.
ΔP = 1 kPa in air: v ≈ 41 m/s.
Icing can give wrong readings.
In more detail
A Pitot tube measures fluid speed by comparing the stagnation pressure at its front with the static pressure along its side. The pressure difference gives the flow speed.
Real-world uses
- Aircraft use Pitot tubes to measure airspeed.
- Wind tunnels use Pitot tubes to measure airflow.
- Aircraft use Pitot tubes to measure airspeed, which is essential for safe flight and landing.
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Frequently asked questions
Why is a Pitot tube important for aircraft?
It provides the airspeed needed for safe flight, and blockage can cause dangerous errors.
What is stagnation pressure?
The pressure at a point where the flow is brought to rest.
What is stagnation pressure?
The pressure at a point where the fluid is brought to rest, which is greater than the static pressure by the dynamic pressure.
Related topics in Fluids & Elasticity
Applications of Bernoulli · Torricelli's theorem · Venturi meter · Lift on a wing · Magnus effect · Viscosity