48-Inch Water Tunnel Turbulence Level Measurements with and without a Honeycomb.

Abstract

The results of turbulence measurements made in the 48-inch diameter water tunnel with and without a honeycomb are reported. Comparison is made to previous measurements made behind a similar honeycomb. It was found that with the honeycomb the average axial turbulence intensity in the test section was 0.11% for tunnel flow velocities between 25 and 60 ft/sec. This value agrees with a previous estimate as well as the current predicted level based on plenum section measurements. The longitudinal integral length scale was estimated as 0.54 inches in the test section. Spectral analysis showed an abnormally high turbulent energy level at a test section velocity of 20 ft/sec; higher flow speeds had spectra with lower levels and the same shape. From spectral and turbulence intensity data, it is recommended that the tunnel be operated at flow speeds between 25 and 60 ft/sec and at an impeller pitch angle of 22.5 deg for minimum turbulence levels. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 28, 1977
Accession Number
ADA042115

Entities

People

  • B. E. Robbins

Organizations

  • Pennsylvania State University

Tags

DTIC Thesaurus Topics

  • Diameters
  • Energy Levels
  • Impellers
  • Integrals
  • Intensity
  • Measurement
  • Spectra
  • Tunnels
  • Turbulence
  • Water Tunnels

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Fluid Mechanics and Fluid Dynamics.
  • Structural Dynamics.