Enhancement Mechanism of Fish-Scale Surface Texture on Flow Switching and Mixing Efficiency in Microfluidic Chips

Abstract

Surface textures have a significant influence on surface-functional properties, which provide an alternative solution to create an accurate control of microfluidics flow. This paper studies the modulation ability of fish-scale surface textures on microfluidics flowing behavior on the ground of the early research on vibration machining-induced surface wettability variation. A microfluidic directional flow function is proposed by modifying the wall of the microchannel at the T-junction with different surface textures. The retention force caused by the surface tension difference between the two outlets in the T-junction is studied. In order to investigate the influence of fish-scale textures on the performance of the directional flowing valve and micromixer, Tshaped and Y-shaped microfluidic chips were fabricated. The experimental results indicated that with the aid of the fish-scale surface textures generated by vibration-assisted micromilling, directional liquid flow can be achieved at a specific input pressure range and the mixing efficiency of microfluidics can be improved dramatically.

The Physics and Manipulation of Dean Vortices in Single- and Two-Phase Flow in Curved Microchannels: A Review

“…At the micro-scale, such as in microfluidics, the channels typically have dimensions in the order of tens to hundreds of micrometers [70,71]. At such a scale, the flow characteristics in the microchannel may exhibit unique behaviors due to the dominance of viscous forces over inertial forces [49,72]. Consequently, the Reynolds number (the ratio of inertial forces to viscous forces) may be much lower in microchannels [65].…”

Theoretical and Experimental Investigation of Surface Textures in Vibration-Assisted Micro Milling

“…This technique overcomes limitations of existing approaches with the benefits of cost-effectiveness, high efficiency, and environmental friendliness. Engineered surface textures produced by vibration-assisted micro milling provide multifaceted performance enhancements, including reduced adhesion friction [ 20 ], smoothed lubricated sliding, upgraded wear resistance [ 21 ], controlled surface wettability [ 22 ], and tuned optical characteristics [ 23 ].…”

Design, Implementation, and Optimization of a Novel Chaotic Micromixer

“…10,16−18 One of the approaches in designing passive micromixers involves creating microchannels with complex shapes to achieve the three-dimensional fusion of microfluidics. 19 Branebjerg et al 20 proposed a multilevel, multilayer composite micromixer. Mixing speed can be accelerated by guiding the stratification of liquids within the mixer to increase the contact area of the liquids to be mixed.…”

“…However, the additional equipment significantly escalates the operational costs, compromising the portability of the chip. Additionally, the imposition of external driving forces unavoidably leads to heat generation within the fluid, potentially causing an undesirable impact on the activity of certain chemical reactions and biomaterials due to the increased temperature. − Passive micromixers promote fluid mixing by changing their own structure and shape to enhance the diffusion effect of fluid molecules and chaotic advection within the microchannels and have many advantages over active micromixers, such as simple fabrication, easy integration, high stability, and low cost. ,− One of the approaches in designing passive micromixers involves creating microchannels with complex shapes to achieve the three-dimensional fusion of microfluidics . Branebjerg et al proposed a multilevel, multilayer composite micromixer.…”