DOI: 10.1615/ICHMT.2006.TurbulHeatMassTransf
ISBN Print: 978-1-56700-229-4
ISSN: 2377-2816
Flow structure of a recirculation zone in a coaxial jet mixer
摘要
Experimental results on velocity and scalar development in the recirculation zone of a coaxial jet mixer of two geometries are presented. The analysis of turbulent characteristics (average velocity and velocity fluctuations, average mixture fraction, rms mixture fraction fluctuations, scalar autocorrelation function, spectra) and flow visualization have revealed the essentially unsteady flow structure of the recirculation zone. It has been shown that the fast scalar mixing is provided by a great number of the local scalar jets, spreading from the mixer axis to the walls, which are generated near the rear boundary of the recirculation zone. These jets also generate the back flow which seems to influence the mixing moderately.