Engelund's analysis of turbulent energy and suspended load

Research output: Contribution to journalArticle

Abstract

We analyze a one-equation model for the turbulent kinetic energy of an open channel flow in the presence of suspension sediment. Engelund's pioneer analysis and his criterion for the threshold conditions for the initiation of suspension are revisited, and it is concluded that such criterion does not represent any physical response of the system under consideration, but rather appears to be an artifact of the mathematical manipulations of the turbulent energy equation. The present analysis indicates that the effect of the suspended sediment on the turbulent kinetic energy near the bed is to reduce such energy when the particle size is sufficiently small, and that the reduction increases with the sediment concentration and the particle settling velocity to flow shear velocity ratio. On the other hand, suspended particles of larger size can enhance the turbulence of the flow because of the production of turbulent kinetic energy through vortex shedding mechanisms. A criterion is proposed to estimate the conditions for which turbulent enhancement due to the presence of suspended sediment occurs.

Original languageEnglish (US)
Pages (from-to)480-483
Number of pages4
JournalJournal of Engineering Mechanics
Volume124
Issue number4
DOIs
StatePublished - Apr 1998

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Kinetic energy
Suspended sediments
Sediments
Open channel flow
Vortex shedding
Shear flow
Turbulence
Particle size

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Engelund's analysis of turbulent energy and suspended load. / Niño, Yarko; Garcia, Marcelo Horacio.

In: Journal of Engineering Mechanics, Vol. 124, No. 4, 04.1998, p. 480-483.

Research output: Contribution to journalArticle

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