Using Helicopters to Clear Fog: A Numerical Study

Abstract

A two-dimensional axial symmetric cloud dynamics model, which uses the Boussinesq approximation form of the equations of motion, was used to study downwash-induced fog clearings. The flow produced by constraining the vorticity to a prescribed value in a small region near the centerline of the model is similar to that observed to occur below a hovering helicopter. Several numerical experiments are discussed which show the efficacy of different hovering altitudes on the clearing of fog. The major feature affecting the size of clearing by helicopter downwash is the size of the primary downwash volume.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1974
Accession Number
AD0777429

Entities

People

  • David B. Johnson
  • Edward H. Barker
  • Paul R. Lowe

Tags

Communities of Interest

  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Aircrafts
  • Altitude
  • Atmospheric Sciences
  • California
  • Combustion
  • Diffusion Coefficient
  • Environment
  • Equations
  • Flow
  • Heat Energy
  • Helicopter Engines
  • Helicopters
  • Latent Heat
  • Military Operations
  • Research Facilities
  • United States
  • Water Vapor

Readers

  • Aerodynamics.
  • Atmospheric Remote Sensing.
  • Control Systems Engineering.