Mixing of confined coaxial flows

Study of scalar macro- and microstructures in a confined jet

“…These facts are clearly seen in the history of the mixture fraction recorded by the PLIF method and from the analysis of the autocorrelation function of the mixture fraction fluctuations across the pipe (see Fig. 5 in Zhdanov et al, 2006).…”

“…A qualitative description of the r-mode is given by Barchilon and Curtet (1964). The large scale flow phenomena in a jet mixer has been the subject of our previous experimental and numerical works (see Kornev et al, 2005;Zhdanov et al, 2006;Hassel et al, 2006;Tkatchenko et al, 2007). Our study showed that the flow in the r-mode is highly unsteady and time averaged results do not describe properly the true nature of flow phenomena typical for this mode.…”

“…The test section of the mixer was installed in a Perspex rectangular box filled with water to reduce refraction effects. More detailed information about the hydrodynamic channel can be found in Zhdanov et al (2006). Since the Reynolds number based on the jet exit velocity U d is Re d ¼ dU d =m ¼ 10 4 the jet can be considered as a fully-developed turbulent jet.…”

“…If D=d < bð1 þ _ V D = _ V d Þ, where b % 1 is an empirical constant found from a simple entrainment model, the flow is similar to a free jet (henceforth referred to as jet-mode or j-mode for short). If D=d > bð1 þ _ V D = _ V d Þ a strong flow separation at the pipe walls results in a recirculation zone (see Fig.7 in Zhdanov et al, 2006) behind the nozzle (henceforth referred to as recirculation-mode or r-mode for short). A qualitative description of the r-mode is given by Barchilon and Curtet (1964).…”

Millisecond mixing of liquids using a novel jet nozzle

“…The two dimensional (2-D) mixing performance can be revealed with high resolution in space. In the recent years, PLIF has been successfully applied to various scientific researches (e.g., Fabrice et al, 2000;René et al, 2003;Hoffmann et al, 2006;Zhdanov et al, 2006) as well as our previous work (Luo et al, 2006(Luo et al, , 2007a. Fig.…”