Pipe friction & head loss worksheet with answers

Free printable Pipe friction & head loss worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
V = 2.25 m/sD = 150 mmρ = 850 kg/m³, μ = 0.005 Pa·s

Light fuel oil (ρ = 850 kg/m³, μ = 0.005 Pa·s) flows at 2.25 m/s through a pipe with an inside diameter of 150 mm. Find the Reynolds number Re.

ρ = 850 kg/m³μ = 0.005 Pa·sV = 2.25 m/sD = 150 mm
Re =
2.Easy
V = 1.75 m/sD = 200 mmρ = 880 kg/m³, μ = 0.04 Pa·s

Hydraulic oil (ρ = 880 kg/m³, μ = 0.04 Pa·s) flows at 1.75 m/s through a pipe with an inside diameter of 200 mm. Find the Reynolds number Re.

ρ = 880 kg/m³μ = 0.04 Pa·sV = 1.75 m/sD = 200 mm
Re =
3.Medium
V = 1 m/sD = 75 mmL = 1000 mf = 0.015

Water flows at a mean velocity of 1 m/s through a pipe 1000 m long with an inside diameter of 75 mm. Use the Darcy friction factor f = 0.015 and g = 9.81 m/s². Find the friction head loss hf.

V = 1 m/sL = 1000 mD = 75 mmf = 0.015g = 9.81 m/s²
hf = m
4.Medium
V = 2.2 m/sD = 200 mmL = 1000 mf = 0.028

Water flows at a mean velocity of 2.2 m/s through a pipe 1000 m long with an inside diameter of 200 mm. Use the Darcy friction factor f = 0.028 and g = 9.81 m/s². Find the friction head loss hf.

V = 2.2 m/sL = 1000 mD = 200 mmf = 0.028g = 9.81 m/s²
hf = m
5.Hard
K = 2free outletH = ?L = 400 m, D = 300 mm, f = 0.024× bend (K = 0.3)

A pipe 400 m long with an inside diameter of 300 mm (Darcy friction factor f = 0.02) runs from an open reservoir and discharges as a free jet into the air. The minor losses are a square-edged entrance (K = 0.5), 4 bends (K = 0.3 each) and a valve (K = 2). Use g = 9.81 m/s². How far H must the reservoir surface be above the pipe outlet for a flow rate of 80 L/s?

Q = 80 L/sL = 400 mD = 300 mmf = 0.02Kentrance = 0.5Kbend = 0.3 (×4)Kvalve = 2
H = m
6.Hard
K = 5Δz = ?L = 100 m, D = 250 mm, f = 0.0182× bend (K = 0.3)

Two open reservoirs are joined by a pipe 100 m long with an inside diameter of 250 mm and a Darcy friction factor f = 0.018. The minor losses are a square-edged entrance (K = 0.5), 2 bends (K = 0.3 each), a valve (K = 5) and the exit into the lower reservoir (K = 1.0). Use g = 9.81 m/s². What difference in water level Δz between the reservoirs gives a flow rate of 50 L/s?

Q = 50 L/sL = 100 mD = 250 mmf = 0.018Kentrance = 0.5Kbend = 0.3 (×2)Kvalve = 5Kexit = 1.0
Δz = m

Answer key

  1. 1. Re = 57375
  2. 2. Re = 7700
  3. 3. hf = 10.19 m
  4. 4. hf = 34.54 m
  5. 5. H = 2.048 m
  6. 6. Δz = 0.7562 m

Full step-by-step solutions: practise this topic on examproblems.com.