How did you come up with the 2" pipe Total head at point D to equal 232. Shouldn't it be 1200ft - 67.2 = 1132ft (at 11:15 in the video)? Thank you for the video. Oops it was corrected at 13:26.
for the above-shown model example, for 55GPM demand/flowrate, may be provided 2" size dia pipeline upto peak point (C) and the pipe size 1.5" to the remaining pipe length to avoid negative pressures at the peak point for 55GPM demand/flowrate. and provide an air valve at peak point (C) in just downstream side of the point (C) to avoid negative pressures at maximum possible gravity flow situations if any.
P = gamma of water x head (height of water) = 62.4 lb/ft3 x h(ft) = P in lb/ft2 (gamma fresh water = 62.4 lb/ft3 at normal temps) converting to psi = 62.4 lb/ft3 x h(ft) x 1 ft2/144in2 ((12in)^2 = 144 in2) 62.4/144 = 0.433 P in psi = 0.433 x h in ft or h in ft = 2.31 x P in psi
