Figure 4-7. Construction of the standard Pitot tube.
d. Pitot tubes are used to determine the velocity pressure contours inside ducts.
These measurements are obtained by connecting the static and total pressure taps of
the Pitot tubes to a manometer, which is an instrument for measuring gas (air) pressure
(see Figure 4-8). Inclined manometers are normally used since they increase the
accuracy and precision, especially for air velocities below 2,000 feet per minute.
Figure 4-8. Pitot tube connected to an inclined manometer.