Example 1
An incompressible fluid with a specific gravity of .80 passes through a 12 inch schedule 40 pipe at a velocity of 4 ft/s with a diameter reduction to 8 inches. What is the velocity head for the reduced pipe diameter?
A)
B)
C)
D)
Example 2
This is a straightforward problem with an item that requires the appropriate tables to lookup as is typical for many PE exam questions. Conservation of mass for incompressible fluids yields the following relationship:
The density of a liquid is the ratio of the density of a substance to the density of a standard, usually water for a liquid or solid, and air for a gas. Therefore, in this case the density of the working fluid is given via:
Using an appropriate table for typical schedule 40 pipe diameters gives the internal diameter of the initial section as 11.94 inches. Substituting into the mass balance equation gives:
