Velocity head in part-full pipe

V^2/2g, in traditional units.

Divide volumetric flow rate by cross-sectional area of pipe filled with water to obtain your water velocity v, then apply formula h = (v^2)/2g.

Hamid:

It's a little more complicated than posters nos 1 and 2 indicate. You need to apply something called Hydraulic Radius to get the equivalent flow area. It would be too long to explain it here, but if you can get Crane Tech Paer 410, it gives a good explanation and formulas you can use to calculate what you need. Try Google, as well, or an engineering website you may know for more. Good Luck

Hank

Hi Hankt,

Thank you for your help. I did search the google and came up with the outcome which posted in discussion on July 9 issue.

Thank you again for your concern.