Head Loss
In any real moving fluid, energy is dissipated due to friction; turbulence dissipates even more energy for high Reynolds number flows. Head loss is divided into two main categories, "major losses" associated with energy loss per length of pipe, and "minor losses" associated with bends, fittings, valves, etc. The most common equation used to calculate major head losses is the Darcy–Weisbach equation. Older, more empirical approaches are the Hazen-Williams equation and the Prony equation.
For relatively short pipe systems, with a relatively large number of bends and fittings, minor losses can easily exceed major losses. In design, minor losses are usually estimated from tables using coefficients or a simpler and less accurate reduction of minor losses to equivalent length of pipe.
Read more about this topic: Hydraulic Head
Famous quotes containing the words head and/or loss:
“An old superstition: If the house is filled with dread, place the beds at head to head.”
—Willis Cooper, and Rowland V. Lee. Maid, Son of Frankenstein, explaining to Mrs. Frankenstein why the bedroom is arranged as it is. (1938)
“Our ego ideal is precious to us because it repairs a loss of our earlier childhood, the loss of our image of self as perfect and whole, the loss of a major portion of our infantile, limitless, ain’t-I-wonderful narcissism which we had to give up in the face of compelling reality. Modified and reshaped into ethical goals and moral standards and a vision of what at our finest we might be, our dream of perfection lives on—our lost narcissism lives on—in our ego ideal.”
—Judith Viorst (20th century)