Study On Mixing Mechanism Of Vicious Liquids In Planar Opposed Jets Reactors

Impinging stream has been widely applied in industrial applications of unit operation for its unique phase transfer characteristics.Considering that in most applications of impinging stream,two fluids with different physical properties are mixed,while water has been often used as the fluid media in the literature,research on mixing processes of fluids with different physical properties is needed.The flow regimes and mixing mechanism of viscous liquids in planar opposed jets reactors have been studied by using a Particle Image Velocimetry,Planar Laser Induced Fluorescence and Image Processing Method.The main contents are summarized as follows:1.The flow behaviors and mixing mechanism of viscous liquids in planar opposed jets reactors were experimentally studied.Effects of the jet Reynolds numbers,the viscosities of fluids and the nozzle separation on flow regime and mixing mechanism are investigated.Results show that the influence of fluid viscosity on flow behavior and mixing mechanism is not obvious.The flow behavior and mixing mechanism in planar opposed jets reactors are also experimentally studied,and the results show that with increases of jet separations,the critical Reynolds number corresponding to the half deflecting oscillation decreases,and the mixing performance of fluids is increased at the same Reynolds number.2.The flow behaviors and mixing mechanism of binary fluids in T-jets reactor were focused on in this paper.Effects of the jet Reynolds numbers and physical properties(viscosity,density)of fluids on flow behavior compared with the mixing of corresponding fluid.The results show that at low Reynolds numbers,the mixing effect of the binary-fluid mixing is better than the single component system as the mixing process is mainly controlled by molecular diffusion and the concentration difference between water and viscous fluids causes fast molecular diffusion.In this work,the critical Reynolds number of binary-fluid mixing is larger than the single component system if the Reynolds numbers of water flow in binary-fluid mixing are regarded as the reference variable.