Mixing in a jet

Figure 6.19 Generation of VUV radiation by resonant frequency mixing in a jet [586]...

Yang WC, Keaims DL, McLain DK. Gas mixing in a jetting fluidized bed. AIChE Symposium Series 80(234) 32-41, 1984a. 

Yang, W. C., Ettehadieh, B., and Haldipur, G. B., Solids Circulation Pattern and Particles Mixing in a Large Jetting Fluidized Bed, AIChE J., 32 1994 (1986)... 

This parallel reaction set was used, for example, by Johnson and Prud homme (2003a) to investigate the quality of mixing in a confined impinging-jets reactor. 

Pipino, M. and R. O. Fox (1994). Reactive mixing in a tubular jet reactor A comparison of PDF simulations with experimental data. Chemical Engineering Science 49, 5229-5241. 

Houcine et al. (64) used a non-intrusive laser-induced fluorescence method to study the mechanisms of mixing in a 20 dm CSTR with removable baffles, a conical bottom, a mechanical stirrer, and two incoming liquid jet streams. Under certain conditions, they observed an interaction between the flow induced by the stirrer and the incoming jets, which led to oscillations of the jet stream with a period of several seconds and corresponding switching of the recirculation flow between several metastable macroscopic patterns. These jet feedstream oscillations or intermittencies could strongly influence the kinetics of fast reactions, such as precipitation. The authors used dimensional analysis to demonstrate that the intermittence phenomenon would be less problematic in larger CSTRs. 

Goldberg, P. M. and Essenhigh, R. H. (1978). Coal combustion in a jet-mix stirred reactor. Proc 1 7th Inter Symposium on Combustion, The Combustion Institute, p. 145-154. 

The holes act as sources and sinks for fluid motion [23], They draw the dye from in the surrounding region and expel it in a jet-like action into other parts of the liquid. These jet-like structures are mainly responsible for mixing. Where flow symmetries delineated by the formation of internal stagnation zones exist, mixing is retarded. Best mixing results are obtained for the five-bubble arrangement. 

The use of free jets for achieving mixing in a vessel without agitators is most often found in one-liquid-phase systems, and their performance also can be identified with a mixing time. The different techniques for such measurement will be described below. 

This chapter mainly concerns mixing and precipitation in a jet. Therefore we illustrate some general scaleup principles by considering a nozzle scale-up based on the combined time constants for mixing (tm), nucleation (tn), and growth (tq), as defined in Section 5. One can classify the precipitation subprocesses from the point of view of their competition with mixing. 

The destabilization (mixing) of a jet flow is desirable in many applications, including combustion, noise suppression at jet engine exhaust, infrared signature reduction of engine exhaust for platform stealth, and employment of a lighter and cheaper material for the lift flap such as that used in C-17 aircraft. 

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