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
Q = 15 L/sD = 75 mmν = 0.801 × 10⁻⁶ m²/s

Water at 30 °C (ν = 0.801 × 10⁻⁶ m²/s) flows through a pipe with an inside diameter of 75 mm at 15 L/s. Find the Reynolds number Re.

Q = 15 L/sD = 75 mmν = 0.801 × 10⁻⁶ m²/s
Re =
2.Easy
V = 0.7 m/sD = 50 mmν = 0.801 × 10⁻⁶ m²/s

Water at 30 °C (ν = 0.801 × 10⁻⁶ m²/s) flows at a mean velocity of 0.7 m/s through a pipe with an inside diameter of 50 mm. Find the Reynolds number Re.

V = 0.7 m/sD = 50 mmν = 0.801 × 10⁻⁶ m²/s
Re =
3.Medium
V = 1.6 m/sD = 100 mmL = 800 mf = 0.03

Water flows at a mean velocity of 1.6 m/s through a pipe 800 m long with an inside diameter of 100 mm. Use the Darcy friction factor f = 0.03 and g = 9.81 m/s². Find the friction head loss hf.

V = 1.6 m/sL = 800 mD = 100 mmf = 0.03g = 9.81 m/s²
hf = m
4.Medium
V = 2.2 m/sD = 50 mmL = 150 mf = 0.022

Water (ρ = 1000 kg/m³) flows at 2.2 m/s through a horizontal pipe, 150 m long, with an inside diameter of 50 mm. Use the Darcy friction factor f = 0.022 and g = 9.81 m/s². Find the pressure drop Δp over the pipe in kPa.

V = 2.2 m/sL = 150 mD = 50 mmf = 0.022ρ = 1000 kg/m³
Δp = kPa
5.Hard
K = 2free outletH = ?L = 100 m, D = 150 mm, f = 0.023× bend (K = 0.3)

A pipe 100 m long with an inside diameter of 150 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), 3 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 20 L/s?

Q = 20 L/sL = 100 mD = 150 mmf = 0.02Kentrance = 0.5Kbend = 0.3 (×3)Kvalve = 2
H = m
6.Hard
K = 0.2Δz = ?L = 100 m, D = 100 mm, f = 0.0183× bend (K = 0.3)

Two open reservoirs are joined by a pipe 100 m long with an inside diameter of 100 mm and a Darcy friction factor f = 0.018. The minor losses are a square-edged entrance (K = 0.5), 3 bends (K = 0.3 each), a valve (K = 0.2) 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 25 L/s?

Q = 25 L/sL = 100 mD = 100 mmf = 0.018Kentrance = 0.5Kbend = 0.3 (×3)Kvalve = 0.2Kexit = 1.0
Δz = m

Answer key

  1. 1. Re = 317912
  2. 2. Re = 43695
  3. 3. hf = 31.31 m
  4. 4. Δp = 159.7 kPa
  5. 5. H = 1.158 m
  6. 6. Δz = 10.64 m

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