Manifold split-and-recombination

Passive mixing Diffusion Contacting of two sub-streams Injection of many sub-streams of two components Manifold splitting and recombination Injection of many small sub-streams of one component in a main stream of another component Decrease of diffusion path perpendicular to the flow... 

Manifold split-and-recombination micromixers are also popular and powerful micromixers. " In this type of micromixer, two solutions to be mixed are introduced into a channel and combined. Then, the mixture is split into two streams in such a way that each stream contains segments of two different solutions. The two streams are then introduced into the next channel and recombined so that the number of solution segments increases, as shown in Figure 7.10. 

Figure 7.10 Principle of a single manifold split-and-recombination operation...

The Toray Hi-mixer is a special type of manifold split-and-recombination micromixer. The structure of the Hi-mixer is shown Figure 7.12. In the Hi-mixer, when two layers of the solutions enter the mixing element, they are split into eight layers by using twist walls in the element. Therefore, in this method, the number of layers increases exponentially by repeating the operation (4" after the wth iteration). 

Figure 7.11 Principle of multiple manifold split-and-recombination operations...

Fig. 3.8 Mixing based on manifold split and recombination of flow segments...

Fig. 3.9 Mixing in a Toray Hi-mixer (a manifold split and recombination-type micromixer)...

In the cross-head type of dies, the melt is split at the inlet to the manifold and recombines 180° from the inlet. Moreover, the flow is not axisymmetric, and fluid particles flowing around the mandrel have a longer distance to travel than those that do not. 

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