Engineering Board Exam Reviewer · Fluid Mechanics · hard

Power transmitted through a pipeline from a reservoir to a nozzle is maximum when the friction head loss in the pipe equals:

  1. One-half of the total available head
  2. Two-thirds of the total available head
  3. The total available head
  4. One-third of the total available head

Answer

D. One-third of the total available head

Solution

P = Q(H - hf) with hf Q2. Setting dP/dQ = 0 gives hf = H/3; the transmission efficiency is then 66.7%.

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