go to:  qna.rediff.com
Click and drag this link to
the Home icon in your browser.
Q.

What is the formula for head loss due to friction?

Tags: money, health, science
Asked by hitler, 01 Jan '10 08:00 pm
4000 characters remaining

1.

The Darcy-Weisbach equation with the Moody diagram are considered to be the most accurate model for estimating frictional head loss in steady pipe flow. Since the approach requires a not so efficient trial and error iteration an alternative empirical head loss calculation like the Hazen-Williams equation may be preferred. source: http://www.engineeringtoolbox.com/hazen-williams-water-d_797.html
The stated source gives an online calculator using Hazen -Williams equation. Manning's formula can also be used for gravity driven flows in open channels.
Answered by Somebodysomewhere, 01 Jan '10 08:11 pm

Report abuse
Useful
(1)
Not Useful
(0)
2.

Fluid statics?
it is darci weibash equation
Answered by sreekumar, 01 Jan '10 08:13 pm

Report abuse
Useful
(1)
Not Useful
(0)
3.

F = 0.2083 (100/c)^1.852 * q^1.852 / dh^4.8655 (1)

where

f = friction head loss in feet of water per 100 feet of pipe (fth20/100 ft pipe)

c = Hazen-Williams roughness constant

q = volume flow (gal/min)

dh = inside hydraulic diameter (inches)
Answered by SHIRISH SHIROOR, 01 Jan '10 08:11 pm

Report abuse
Useful
(1)
Not Useful
(0)