Library Subscription: Guest
TSFP DL Home Archives Executive Committee

MEASUREMENTS OF DIFFERENTIAL DIFFUSION EFFECTS IN TURBULENT MIXING

Cody J. Brownell
Department of Mechanical Engineering The Johns Hopkins University Baltimore, Maryland 21218, USA

Lester K. Su
Johns Hopkins University, Department of Mechanical Engineering, Baltimore, MD, USA

Abstract

Measurements of differential molecular diffusion in a propane-helium jet flowing into air are performed using planar Rayleigh scattering. A comprehensive data set has been obtained for two flow conditions, one at a jet Reynolds number of 1000 and the other at a Reynolds number of 2500. Observations show clear evidence of differential diffusion, particularly in the low Reynolds number case. The standard differential diffusion variable, ε, is computed and profiles of εrms show similiar features to previous 1-D measurements.