Mixing dynamics of turbidity currents interacting with complex seafloor topography

Mohamad M. Nasr-Azadani, Eckart Meiburg, Benjamin Charles Kneller

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Direct Numerical Simulations are employed to investigate the mixing dynamics of turbidity currents interacting with seamounts of various heights. The mixing properties are found to be governed by the competing effects of turbulence amplification and enhanced dissipation due to the three-dimensional topography. In addition, particle settling is seen to play an important role as well, as it affects the local density stratification, and hence the stability, of the current. The interplay of these different mechanisms results in the non-monotonic dependence of the mixing behavior on the height of the seamount. Regions of dilute lock fluid concentration generally mix more intensely as a result of the seafloor topography, while concentrated lock fluid remains relatively unaffected. For long times, the strongest mixing occurs for intermediate bump heights. Particle settling is seen to cause turbidity currents to mix more intensely with the ambient than gravity currents.
Original languageEnglish
Pages (from-to)201 -223
Number of pages23
JournalEnvironmental Fluid Mechanics
Volume18
Issue number1
Early online date2 Aug 2016
DOIs
Publication statusPublished - Feb 2018

Fingerprint

turbidity current
Turbidity
Topography
seafloor
topography
particle settling
seamount
Fluids
fluid
Direct numerical simulation
Amplification
dissipation
amplification
Gravitation
stratification
Turbulence
turbulence
gravity
simulation

Keywords

  • gravity current
  • turbidity current
  • mixing
  • particle setting
  • numerical simulations
  • complex topography

Cite this

Mixing dynamics of turbidity currents interacting with complex seafloor topography. / Nasr-Azadani, Mohamad M.; Meiburg, Eckart; Kneller, Benjamin Charles.

In: Environmental Fluid Mechanics, Vol. 18, No. 1, 02.2018, p. 201 -223.

Research output: Contribution to journalArticle

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