Figure 4: A staggered herringbone mixer (SHM)
A mixing cycle is composed of two sequential regions of ridges. The streamlines of the flow in the cross section are shown above the channel. The angle, delta-phi m, is the average angular displacement of a volume of fluid along an outer streamline over one half cycle. Below are confocal micrographs of vertical cross sections of a channel. Two streams of fluorescent solution were injected on either side of a stream of clear solution; the fingerlike structures are due to the weak separation of streamlines that occurs in the rectangular grooves. Here, h=77 um, w=200 um, alpha=0.23, 10 ridges per half cycle.