Mixing pp 287-295 | Cite as

The effect of Schmidt Number on Stratified Entrainment

  • Aline J. Cotel
Part of the NATO ASI Series book series (NSSB, volume 373)


From a review of the literature, including a new theory on vortex persistence, the effect of Schmidt (or Prandtl) number on stratified entrainment is discussed. In contrast to unstratified turbulence, stratified turbulence entrainment depends on diffusive properties of the stratifying agent. Stratification inhibits the large scale motions of the flow which would otherwise dominate entrainment, so that smaller scale processes become important. At sufficiently large Richardson number, the diffusion of solutal (or heat) at small scales determines the entrainment rate. Thus stratification can act as a probe of the turbulence, suppressing normally dominant features to reveal weaker, more subtle effects.


Prandtl Number Richardson Number Schmidt Number Entrainment Rate Small Eddy 
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Copyright information

© Springer Science+Business Media New York 1999

Authors and Affiliations

  • Aline J. Cotel
    • 1
  1. 1.Department of Mechanical and Industrial EngineeringUniversity of ManitobaWinnipegCanada

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