What does a Pitot tube measure?

What does a Pitot tube measure?

• A. Velocity of low to medium gas flow applications
• B. Temperature of the fluid
• C. Electrical pressure
• D. Flow rate of liquids

Answer: (A)

Pitot tubes work by turning the fluid’s motion into a pressure difference. The opening facing into the flow captures stagnation pressure, while a separate port measures static pressure. The difference between these pressures is dynamic pressure, which, for gases at typical speeds, relates to velocity through the equation dynamic pressure = 0.5 × density × velocity squared. From that you solve for velocity, so the device directly provides how fast the gas is moving. That’s why it’s used for measuring velocity in low to moderate gas flow applications. It doesn’t measure temperature, nor does it quantify any electrical pressure. It also doesn’t directly give flow rate; to get flow rate you’d multiply velocity by the flow area (and account for density if needed).

Pitot tubes work by turning the fluid’s motion into a pressure difference. The opening facing into the flow captures stagnation pressure, while a separate port measures static pressure. The difference between these pressures is dynamic pressure, which, for gases at typical speeds, relates to velocity through the equation dynamic pressure = 0.5 × density × velocity squared. From that you solve for velocity, so the device directly provides how fast the gas is moving.

That’s why it’s used for measuring velocity in low to moderate gas flow applications. It doesn’t measure temperature, nor does it quantify any electrical pressure. It also doesn’t directly give flow rate; to get flow rate you’d multiply velocity by the flow area (and account for density if needed).