Numerical characterisation of folding flow microchannel mixers

Analysis of a pressure‐driven folding flow microreactor with nearly plug‐flow characteristics

“…[8][9][10] Recent progress in the microfluidic technology has turned the research's attention to the RTD in the microdevices, usually operated under laminar regimes. [11][12][13][14][15] Although some dispersion is unavoidable, it can be significantly suppressed by proper design of the mixer element and its effect on the outcome of chemical reactions occurring in the flow can be effectively controlled. In Section 2, we discuss the Taylor dispersion in a microdevice consisting of series of identical elements.…”

“…Although the results presented below hold for any chaotic micromixer with spatially periodic geometry, we will look quantitatively at particular element geometry: a folding flow micromixer operated under Stokes conditions. 15 The schematic view of the mixer is presented in Figure 1. Two elements are shown, each serving to split the flow and then recombine it such that (approximately) the interface area between two initially segregated streams is doubled and the striation thickness is halved.…”

“…This severe limitation becomes more obvious if one considers the pressure drop required to drive the fluid through the channel. The pressure drop along a single element is as follows 15 :…”

“…So, a single step achieves an approximation of the baker's transformation. [15][16][17][18] The volume and length of each element of the channel are V 0 and l 0 , respectively. The mean residence time of the liquid inside the element and the mean velocity can be defined as follows:…”

Design Principles for Microfluidic Biomedical Diagnostics in Space

“…Complete mixing over a shorter length can be achieved if additional incentives are introduced, such as convective motion. Convective mixing is added through geometry by channel bending, twisting, and flattening (MacInnes et al, 2007). However, these convoluted flow paths come at the price of increased flow resistance, which imposes increased power requirements (Hsu et al, 2008).…”