Interactive Self-Study Module: Calculating Length and Equivalent Length in a Pipe


This module uses screencasts to introduce the concept of equivalent length and its relationship to loss coefficients. Included are screencasts that give simple examples of length and equivalent length through equations and simple examples. Your retention of material in this module will increase if you write down reasons for your answers to ConcepTests, questions in screencasts, and you try to solve the example problems before watching the screencast solutions. We suggest using the learning resources in the following order:

  1. Attempt to answer the multiple-choice ConcepTest and solve the example problem before watching the screencast.
  2. Watch the screencast that provides an introduction to equivalent length.
  3. Try to solve the example problem before watching the solution in the screencast.
  4. Answer the ConcepTest.
  5. Look at the list of key points, but only after you try to list the key points yourself.
  • Equivalent length is a simple way to compare the effect of minor head loss to that of major head loss. 
  • This module is intended for fluid mechanics courses.
Before studying this module, you should be able to:
  • Explain the concept of the Reynolds number (Re) and be able to calculate it.
  • Use the Moody chart.
  • Simplify the energy equation.
After studying this module, you should be able to:
  • Calculate the pipe length that produces a certain amount of major head loss.
  • Relate equivalent length to minor head loss.
  • Calculate equivalent length for a simple system.