Use this Pitot tube calculator to determine air velocity from total pressure, static pressure, and air density using Bernoulli’s equation.
Step-by-step calculation:
A Pitot tube is an instrument designed to measure the velocity of a fluid, such as air or water, by comparing the total pressure and the static pressure. It is widely used in aviation to determine airspeed, as well as in industrial and HVAC applications to calculate flow rates accurately.
Accurate measurement of fluid velocity is critical for:
The velocity of air can be determined from the pressure difference:
v = √(2 (P_total − P_static) / ρ)
The volumetric flow rate can be calculated using:
Use the calculator below to quickly determine airspeed and volumetric flow rate for your application.
Suppose a Pitot tube measures a total pressure of 1200 Pa and a static pressure of 1000 Pa in an air stream with density 1.2 kg/m³. Using the calculator, you can find:
A Pitot tube is used to measure the velocity of a fluid by comparing the difference between total pressure and static pressure. This pressure difference is called the dynamic pressure and can be used to calculate the velocity of the fluid using Bernoulli’s equation.
Pitot tubes are widely used in aviation to measure aircraft airspeed, as well as in industrial ducts, wind tunnels, and HVAC systems to determine airflow velocity. Because they are simple, reliable, and accurate, they remain one of the most commonly used instruments for measuring flow velocity in gases and liquids.
Yes, Pitot tubes can be used to measure liquid flow, although they are most commonly applied to air and gas measurements. In liquids such as water or oil, the Pitot tube works in the same way by measuring the difference between total pressure and static pressure. However, special care must be taken to avoid clogging or contamination of the measurement ports.
In industrial applications, Pitot tubes are often used in pipelines, hydraulic testing setups, and water channels where accurate velocity measurements are needed without significantly disturbing the flow.
Yes, air density plays a crucial role in Pitot tube calculations. The velocity of the fluid is determined using the equation:
v = √(2ΔP / ρ)
where ΔP is the dynamic pressure and ρ is the fluid density. Because density appears in the denominator, any change in air density will directly influence the calculated velocity.
Air density varies depending on temperature, altitude, humidity, and atmospheric pressure. For example, aircraft flying at high altitude must account for lower air density when computing true airspeed from Pitot tube measurements.
Pitot tubes are widely used in many engineering and scientific applications where fluid velocity needs to be measured accurately. The most well-known application is in aviation, where Pitot tubes are installed on aircraft to measure airspeed during flight.
Other common applications include:
Because of their simplicity and reliability, Pitot tubes remain one of the most widely used tools for measuring fluid velocity in both gases and liquids.
Want to explore more tools? Check out our full collection of Fluids Calculators to enhance your learning and research.
Since we can offer a large number of related Fluid mechanics calculators, you can chose which one serves your needs below: