What is the normal viscous force(stress)?

  1. Hello,

    I understand the tangential shear stresses (or forces) acting on a fluid element due to friction between moving fluid layers, but I can't imagine how viscosity might cause a normal force (on a fluid element)....explain please!
  2. jcsd
  3. boneh3ad

    boneh3ad 1,946
    Science Advisor
    Gold Member

    Who ever said that it did? Viscosity can only cause normal stresses in a compressible flow where the divergence of the velocity field is nonzero. This is, however, bulk viscosity rather than the typical dynamic viscosity.
Know someone interested in this topic? Share this thead via email, Google+, Twitter, or Facebook

Have something to add?