Compact mixing using multiple splitting, stretching, and recombining flows

The working principle of static mixers is based on repeated stretching, cutting, and stackingoperations. Two-way splitting (cutting) elements are most commonly used. Multiple splittingelements increase the compactness of the mixer, but an issue is the pressure consumption.Here we first investigate how to improve existing two way splitting and recombining flows.We use the serpentine channel geometry which relevance is that it is easy to fabricate on theinterface between two halves of a mold or device. Next a parallel multiple splitting method isdeveloped which is compact and efficient in terms of pressure consumption and uniformity ofthe resulting layer distribution. The final design represents a fully parallel multiple mixer,circularly shaped, that uses fan shaped channels (for a uniform flow length distribution) toguide the flow to its splitting channels, where it is turned and recollected in a second fanshaped channel. Because of its twelve-way parallel splitting design, the device produces 24layers in one mixing element and 288 layers in the second element and so on. Prototypes arefabricated, tested on performance, and compared with some existing static mixers usingmixing speed, volume, length, and pressuredrop as criteria. The new mixer outperformsthe other designs, with an exceptionof the volume used.