Accession Number : AD0276521

Title :   AN EXPERIMENTAL STUDY OF THE DECAY OF TURBULENT ENERGY IN SEVERAL GASES AND AT HIGH AND LOW DENSITY

Corporate Author : PRINCETON UNIV N J JAMES FORRESTAL RESEARCH CENTER

Personal Author(s) : WEBB,W.H.

Report Date : JAN 1962

Pagination or Media Count : 1

Abstract : A hot-wire anemometer study of the decay of turbulent energy downstream of a grid in atmospheric pressure air, argon and helium and at several ambient pressure levels in air was carried out. A variable density low speed blowdown tunnel was employed which was operated over the range 0.2 to 8 atmospheres pressure. It was found in the decay measurements that above a grid Reynolds number, RM, of about 2,000 and at atmospheric pressure and above, an identical initial period decay law occurred independent of the gas employed or the ambient pressure level. There was no evidence indicating the invalidity of the continuum view of turbulence for this range. For RM below 1,000 or at low ambient pressure, however, a decrease in the normal turbulence intensity was found, the magnitude of which appeared to depend on the pressure level and the gas employed. (Author)

Descriptors :   *TURBULENCE, AIR, ANEMOMETERS, ARGON, DENSITY, FLUID MECHANICS, HELIUM, PRESSURE, REYNOLDS NUMBER

Distribution Statement : APPROVED FOR PUBLIC RELEASE