Grooved mixer

Mixer type Oblique, straight-grooved mixer Channel width at top and bottom, depth 72 pm, 28 pm, 31 pm... 

M 80] [P 70] From prior experience with the chaotic screw extruder, it was estimated that the presence of the barrier structures in the barrier-embedded mixer accounts for about a 10% reduction in flow rate as compared with the slanted grooved mixer [58], Thus, a large mixing improvement is given at the cost of only a small reduction in flow rate. 

Figure 2.42 Micro mixer geometry with staggered groove structures on the bottom wall, as considered in [137], The top of the figure shows a schematic view of the channel cross-section with the vortices induced by the grooves. At the bottom, confocal micrographs showing the distribution of two liquids over the cross-section are displayed.

Mixer type Non-grooved micro Channel width, 200 pm, 70 pm... 

Mixer 75 [M 75] Oblique, Straight-grooved Micro Mixer (I)... 

The main feature of this class of mixers is patterned grooves on the floor of the micro channel [44], In the simplest version, the array of grooves presents a repeating, periodic sequence of the base structure. In the following, one typical set of design specifications is given. 

Mixer 76 [M 76] Oblique, Asymmetrically Grooved Micro Mixer-Staggered Herringbone Mixer (SHM)... 

A mixer, which is part of a sensor system, has diagonal grooves on the channel bottom [142], This creates a lateral flow enlarging the interfacial area. No indication is given whether this measure causes the flow to become chaotic. 

M 75] [P 66] 3-D twisting flow is found for a mixer design with an array of multiple obliquely oriented, straight grooves [44]. 

Mixer 80 [M 80] Barrier-embedded Micro Mixer with Slanted Grooves... 

In this barrier-embedded micro mixer, oblique grooves, placed at the channel s floor, and barrier structures at the channel ceiling replace the flights and barriers of the chaos screw [58], The placement of the structures, however, is not essential for the functions. The positions at the floor and ceilings may change without loss of performance two-sided structures are expected to exhibit improved mixing over single-sided structures. The barriers are placed periodically so that barrier-free zones intersect. 

Mixer type Barrier-embedded micro mixer with slanted grooves Groove tilt angle 45°... 

Figure 1.166 Normalized average intensity changes along the down-channel direction of three micro-mixer devices with barrier-embedded, slanted grooved and T-channel structures at (a) Re = 0.228, (b) 0.457, (c) 0.685 and (d) 2.28 [58] (by courtesy of IOP Publishing Ltd ).

Figure 1.167 (a) Characteristic mixing length of all three micro devices and (b) detailed view of the mixing length of the barrier embedded and slanted grooved micro mixers only, as a function of the flow regime, (c)... 

M 80] [P 70] Cross-sectional images of the flow patterns, gained by confocal microscopy, demonstrate the interfacial stretching and hence are indicative of mixing in the barrier-embedded mixer [58], At the non-barrier entrance structure clearly the helical flow induced by the slanted grooves is evident. In the barrier... 

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