Meeting Report: From Stirring to Mixing in a Stratified Ocean

Abstract

Over fifty years ago, Carl Eckart described the sequence of processes as a passive scalar is stirred and mixed in a turbulent flow (Eckart, 1948). At first, during the stirring phase, the variance of the scalar gradient is greatly increased, but later, during the mixing phase, the gradients become sufficiently sharp that molecular diffusion becomes important and the gradient variance rapidly decreases. The process is of great practical importance in many engineering situations as well as being familiar from adding cream to coffee. The interplay of stirring and mixing is also important in the ocean for temperature, salinity, chlorophyll and other naturally occurring tracers as well as for introduced material. The situation is complicated by the numerous physical processes that can cause stirring and by the interplay of processes that act along isopycnals (surfaces of constant mean density, where mean requires careful definition) with "diapycnal" processes acting across the density surfaces.

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Document Details

Document Type
Technical Report
Publication Date
Jan 19, 2001
Accession Number
ADP013596

Entities

People

  • Chris Garrett
  • Peter R. Müeller

Organizations

  • University of Hawaiʻi System

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Buoyancy
  • Diffusion
  • Earth Sciences
  • Flow
  • Fluid Dynamics
  • Fluid Mechanics
  • Internal Waves
  • Mixing
  • Ocean Currents
  • Oceans
  • Physics Laboratories
  • Reynolds Number
  • Sea Water
  • Turbulence
  • Turbulent Flow
  • Turbulent Mixing
  • Two Dimensional

Readers

  • Combustion science or combustion engineering.
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Systems Analysis and Design