From Munson 5th edition Chapter 7 - Northwestern University

head_loss = (delta P)/(gamma) - (length of pipe)(sin theta) head_loss = ( f * (length of pipe/D) * (V^2/2g) ) Equation 1 is just the mechanical energy equation for a pipe tilted at angle theta with no shaft work, with average velocity 1 = average velocity 2. ................
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