Accession Number:

ADA179648

Title:

Measurement of Separate Velocity, Pressure, and Temperature Components in Turbulent Nitrogen Supersonic Flows.

Descriptive Note:

Final technical rept. 15 May 83-14 Aug 84,

Corporate Author:

PRINCETON UNIV NJ DEPT OF MECHANICAL AND AEROSPACE ENGINEERING

Personal Author(s):

Report Date:

1985-06-01

Pagination or Media Count:

29.0

Abstract:

A computer model is used to simulate the measurement of fluctuating flow properties using resonant Doppler velocimetry. A narrow linewidth laser excites fluorescence from sodium atoms which are seeded into a nitrogen flow. The sensitivity of the fluorescence to fluctuating flow parameters as a function of laser wavelength is different for each flow parameter. Thus, a scan of the laser wavelength allows separate measurement of the time averaged fluctuations of velocity, temperature, and pressure. Computer fits to simulated fluorescence profiles from flows with randomly generated fluctuating parameters are shown to accurately reproduce the mean and standard deviations of each separate parameter. Cross correlations are also extracted, but with less accuracy due to largely to truncation error in the computer fitting routine. Keywords Turbulence Laser induced fluorescence Sodium seeding Flow diagnostics Resonant Doppler velocimeter Computer simulation.

Subject Categories:

  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE