Bernoulli's Equation: Summary

The answers to the ConcepTests are given below and will open in a separate window. 
Key points from this module:
  1. Bernoulli’s equation is an energy equation derived from Newton’s second law.
  2. Bernoulli’s equation assumes incompressible, inviscid, steady-state flow along a streamline.
  3. When flow is from a very large diameter into a small diameter, the entering velocity can be considered negligible.
  4. Bernoulli’s equation can be applied to many situations, such as free jets, siphons, and variable area pipes.
  5. Although gases are not usually considered to be incompressible, Bernoulli’s equation can be used when the velocity of the fluid divided by the speed of sound (the Mach number) is less than 0.3.
From studying this module, you should now be able to:
  • Know where to apply Bernoulli’s Equation in a system.
  • Make assumptions based on the physical nature of the problem.
  • Use Bernoulli’s equation to find velocity, pressure, and/or height at any point in the system.
  • Use the continuity equation in conjunction with Bernoulli’s equation to relate two velocities.
Prepared by Janet deGrazia, Department of Chemical and Biological Engineering, University of Colorado Boulder