The horizontal constricted pipe illustrated in Figure 14.20, known as a Venturi tube, can be used to measure the flow
speed of an incompressible fluid. Determine the flow speed
at point 2 if the pressure difference P - P2 is known.
Р
P2
Courtesy of Central Scientific Company
Az
A
(a)
(b)
Figure 14.20 (Example 14.9) (a) Pressure P, is greater than
pressure P, because my <12. This device can be used to mea-
sure the speed of fluid flow. (b) A Venturi tube, located at the
top of the photograph. The higher level of fluid in the middle
column shows that the pressure at the top of the column, which
is in the constricted region of the Venturi tube, is lower