Premium
On the 2D nature of flow dynamics in opposed jets mixers
Author(s) -
Gonçalves Nelson D.,
Salvador Hélder M.,
Fonte Cláudio P.,
Dias Madalena M.,
Lopes José Carlos B.,
Santos Ricardo J.
Publication year - 2017
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.15566
Subject(s) - turbulence , mechanics , vortex , mixing (physics) , flow (mathematics) , energy cascade , turbulence kinetic energy , physics , cascade , injector , chemistry , thermodynamics , chromatography , quantum mechanics
Confined impinging jets (CIJs) are reactors used in processes that require fast mixing. In such equipment two fluids are injected from opposite sides of a chamber, impinging into each other and forming flow structures that enable an effective mixing and reaction. The turbulence analysis shows that the energy is injected from smaller scales, having approximately the injectors width, that feed larger scale structures up to larger vortices that occupy the entire mixing chamber width. This energy distribution has an inverse energy cascade, i. e. it is an inversion of the traditional description of homogeneous 3D turbulence. The typical flow scales of 2D CIJs are clearly shown in this work to be linked to the 2D turbulence energy spectrum and to integral scales of turbulence. Moreover, the turbulence mechanisms in 3D CIJs at transitional flow regimes are shown to be similar to 2D CIJs. This is to our knowledge the first demonstration of 2D turbulence in an industrial mixer/reactor. © 2016 American Institute of Chemical Engineers AIChE J , 63: 2335–2347, 2017