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Viscous Flow

Ground Water Hydrology

  1. Navraj S. Hanspal1,
  2. Vahid Nassehi1,
  3. Diganta Bhusan Das2

Published Online: 15 APR 2005

DOI: 10.1002/047147844X.gw1231

Water Encyclopedia

Water Encyclopedia

How to Cite

Hanspal, N. S., Nassehi, V. and Das, D. B. 2005. Viscous Flow. Water Encyclopedia. 5:555–561.

Author Information

  1. 1

    Loughborough University, Loughborough, United Kingdom

  2. 2

    Oxford University, Oxford, United Kindom

Publication History

  1. Published Online: 15 APR 2005


This text describes the elementary concepts of viscous fluid flow. The principal laws that govern the motion of fluids are also discussed. From our common experience, we know that fluids deform under the action of external forces. The deforming forces and rate of deformation are related to each other through a proportionality constant known as the coefficient of viscosity. The value of this constant depends upon the chemical identity, material properties, and thermodynamic state of a given fluid. To develop a theory that shows how viscosity affects fluid dynamics, one must understand the relationships between stress and the rate of strain. The outlines given in this article provide basic concepts of viscous flow. For more detailed analysis, the reader should consult specialized texts on this topic. Some of these texts are listed in the references at the end of this article.


  • viscosity;
  • non-Newtonian fluids;
  • shell momentum balance;
  • stress;
  • Navier–Stokes equations;
  • Stokes' equation