### 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 language | English |
---|---|

Title of host publication | In: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford, |

Place of Publication | In: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford, |

Pages | 173-188 |

Number of pages | 15 |

Publication status | Published - 2001 |

### Keywords

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

### Cite this

*In: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford,*(pp. 173-188). In: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford,.

**Turbulence structure in steady, solute-driven gravity currents.** / Buckee, C. M.; Kneller, Benjamin Charles; Peakall, J.

Research output: Chapter in Book/Report/Conference proceeding › Chapter

*In: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford,.*In: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford, pp. 173-188.

}

TY - CHAP

T1 - Turbulence structure in steady, solute-driven gravity currents

AU - Buckee, C. M.

AU - Kneller, Benjamin Charles

AU - Peakall, J.

PY - 2001

Y1 - 2001

N2 - 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.

AB - 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.

KW - PLANE WALL-JET

KW - TURBIDITY CURRENTS

KW - VERTICAL STRUCTURE

KW - DENSITY CURRENTS

KW - SEDIMENT

KW - FLOW

KW - DYNAMICS

KW - VELOCITY

KW - HEAD

KW - ENTRAINMENT

M3 - Chapter

SN - 0-6320-5921-4

SP - 173

EP - 188

BT - In: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford,

CY - In: Particulate Gravity Currents, (eds. McCaffrey,W. D.;Kneller,B. C.;Peakall,J.), Blackwell, Oxford,

ER -