Flow Visualization of Time-Varying Structural Characteristics of Dean Vortices in a Curved Channel

Abstract

The time varying development and structure of Dean vortices were studied using flow visualization. Observations were made over a range of Dean numbers from 40 to 200 using a transparent channel with mild curvature, 40:1 aspect ratio, and an inner to outer radius ratio of 0.979. Seven flow visualization techniques were tried but only one, a wood burning smoke generator, produced usable results. Different vortex characteristics were observed and documented in sequences of photographs spaced one quarter of a second apart at locations ranging from 85 to 135 degrees from the start of curvature. Evidence is presented that supports the twisting/rocking nature of the flow. keywords: Curved heat transfer; Centrifugal instabilities.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1988
Accession Number
ADA203875

Entities

People

  • David W. Bella

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acquisition
  • Army Aviation
  • Aspect Ratio
  • California
  • Cameras
  • Combustion
  • Engineering
  • Flow Visualization
  • Heat Transfer
  • Hydrodynamics
  • Liquid Crystals
  • Measurement
  • Mechanical Engineering
  • Photographs
  • Smoke Generators
  • Test Facilities
  • United States

Fields of Study

  • Engineering

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Rocket Propulsion.

Technology Areas

  • Space
  • Space - Hall-Effect Thruster