Mixing Enhancement in a Coaxial Jet Mixer

Valery Zhdanov, Egon Hassel

Rostock University Department of Technical Thermodynamics 18059 Rostock, Germany.
Rostock University Department of Technical Thermodynamics 18059 Rostock, Germany.

DOI: 10.4236/ampc.2012.24B035                

Abstract

Experimental investigations of mixing in a coaxial jet mixer have been carried out applying Particle Image Velocimetry (PIV) and Planar Laser Induced Fluorescence (PLIF) methods simultaneously. A developed turbulent jet of an aqueous solution of Rhodamine 6G issued from the nozzle was mixed with co-flow water. Velocity and scalar fields were studied quite far downstream flow to control the formation of a quasi homogeneous mixture. The intensity of mixing was varied by mouthpieces with rectangular and triangular vortex generators of different sizes installed in the nozzle. The formation length of the quasi homogeneous mixture was reduced about 10 jet diameters by the tabs. The triangular tabs were more effective than the rectangular ones.

Keywords

Mixing; Turbulent Flow; Vortex Generators; PIV; PLIF

Conflicts of Interest

The authors declare no conflicts of interest.

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