Dust, Sand, and Turbulence: Transport and Feedback in the Near Surface Environment

Abstract

A key challenge in modeling dust and sand transport throughout the atmosphere lies in the fundamental particle-turbulence interactions which take place in the lower atmospheric boundary layer. The subsequent airborne spatial distributions, lofting and settling mechanisms, and effects on the surface layer winds remain severely understudied and inhibit prediction in Army-relevant regions of the boundary layer. Phenomena such as preferential concentration, where particles dynamically collect in certain regions of the flow, and two-way coupling, where the suspension of the particles modifies the surrounding turbulent motions, can cause sharp deviations of near-surface concentrations and fluxes from those predicted by traditional, similarity-based parameterizations of passive scalars. While these mechanisms have been studied in numerous engineering contexts, these are typically restricted to low Reynolds numbers (i.e., low degrees of scale separation), and therefore much remains unknown about particle transport and feedback in systems with Reynolds numbers relevant to the atmospheric surface layer.

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Document Details

Document Type
Technical Report
Publication Date
Aug 26, 2022
Accession Number
AD1201064

Entities

People

  • David H Richter

Organizations

  • University of Notre Dame

Tags

DTIC Thesaurus Topics

  • Airborne
  • Boundaries
  • Boundary Layer
  • Channel Flow
  • Computational Fluid Dynamics
  • Detection
  • Feedback
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Froude Number
  • High Resolution
  • Large Eddy Simulation
  • Layers
  • Markov Chains
  • Particles
  • Physics Laboratories
  • Reynolds Number
  • Simulations
  • Spatial Distribution
  • Stratified Fluids
  • Surface Transportation
  • Transport Ships
  • Turbulence
  • Turbulent Boundary Layer
  • Turbulent Flow
  • Wind Tunnels

Fields of Study

  • Environmental science

Readers

  • Aerosol Science/Aerosol Physics
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Systems Analysis and Design