The Characterization of Grid Turbulence for Turbulent Impaction Experiments.
Abstract
An Eulerian description of the turbulent flow field produced by passing air through a uniformly spaced square-mesh grid was characterized by measurements of the relative intensity of the longitudinal velocity fluctuations and the autocorrelation function at various distances from the grid. The autocorrelation functions were analyzed to discern the classical Taylor microscale and macroscale in the turbulent flow. The microscale of turbulence was also obtained from the mean square of the time differentiation of the hot-wire anemometer output for comparison. A graphical analytical Fourier transform technique was used to obtain the turbulent energy distribution of the flow field. The experiments were carried out in a 24 by 30 by 72-inch test section of a low-speed, open-circuit wind tunnel. Four periodic square mesh grids have been characterized: a 3- and 4-inch-mesh monoplane grid with 1-inch-diameter rods; a 1.375-inch-mesh monoplane grid with 0,375-inch-diameter rods, and a 0.625-inch-mesh biplane grid with 0.125-inch-diameter rods.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1976
- Accession Number
- ADA033470
Entities
People
- William A. Cooper