Standard Article

Measurement and Instrumentation of Flow

  1. Francis R. Ruppel1,
  2. James E. Hardy2

Published Online: 15 MAR 2011

DOI: 10.1002/3527600434.eap225.pub2

Encyclopedia of Applied Physics

Encyclopedia of Applied Physics

How to Cite

Ruppel, F. R. and Hardy, J. E. 2011. Measurement and Instrumentation of Flow. Encyclopedia of Applied Physics. 157–194.

Author Information

  1. 1

    Alstom Power Inc., Knoxville, TN, USA

  2. 2

    Engineering Science and Technology Division, Managed by UT-Battelle, LLC, for the U.S. Department of Energy, under contract DE-AC05-00OR22725, Oak Ridge, TN, USA

Publication History

  1. Published Online: 15 MAR 2011


The measurement of flow has received much interest over the years by engineers, researchers, and scientists. Flowmeters, sensors, and instrumentation have been developed for measuring just about any kind of flow under any condition, including gases, vapors, liquids, solids, two-phase flow, and even three-phase flow. The selection of an appropriate flowmeter or sensor is both an art and a science. This article is a review of some of the more common flow measurement methods, their applications, advantages, and disadvantages. Additionally, some causes of measurement uncertainty as well as some calibration techniques are discussed. Most of the measurement methods covered are for closed-pipe flow, with a brief discussion concerning open-channel flow. The flow of solids and multiphase flow are not discussed.


  • flow meters;
  • flow calibration methods;
  • flow uncertainties;
  • differential pressure flow meters;
  • mass flow;
  • volumetric flow