Turbulence structure in steady, solute-driven gravity currents

C. M. Buckee, Benjamin Charles Kneller, J. Peakall

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

High-resolution turbulence data from refractive index-matched gravity currents have been used to quantify the mean flow and turbulence structure in steady, experimental gravity currents. Comparison of this data-set with experimental and theoretical gravity current data from the literature and with turbulent wall jets, reveals several new insights into both subcritical and supercritical flows. Existing data collapse approaches can be improved with the use of a new characteristic lengthscale taken from the wall jet literature. Turbulence production from shear has been quantified and is seen to be most significant in subcritical currents. Density stratification is also shown to be an important control on the distribution of turbulent kinetic energy. A slow diffusion zone (SDZ) characterized by low turbulence intensities and reduced vertical mass transport in the lower part of the current, around the level of the velocity maximum, has been identified, and related to both density stratification and reduced turbulence production around the velocity maximum. The results presented in this chapter should lead to improved understanding of gravity current dynamics and provide a good test for the output of numerical models.

Original languageEnglish
Title of host publicationIn: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford,
Place of PublicationIn: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford,
Pages173-188
Number of pages15
Publication statusPublished - 2001

Keywords

  • PLANE WALL-JET
  • TURBIDITY CURRENTS
  • VERTICAL STRUCTURE
  • DENSITY CURRENTS
  • SEDIMENT
  • FLOW
  • DYNAMICS
  • VELOCITY
  • HEAD
  • ENTRAINMENT

Cite this

Buckee, C. M., Kneller, B. C., & Peakall, J. (2001). Turbulence structure in steady, solute-driven gravity currents. In In: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford, (pp. 173-188).