Microchannels
Microchannels are fluidic passages with cross-sectional dimensions in the micrometer to sub-millimeter range, typically tens to hundreds of micrometers in hydraulic diameter. They enable confinement and precise handling of small fluid volumes, and their high surface-to-volume ratio enhances heat and mass transfer relative to macro channels. In most microchannels, flow is laminar (low Reynolds number) and driven by pressure differences or electrokinetic effects.
Common geometries include rectangular and circular cross-sections, with straight, serpentine, or folded layouts to maximize residence
Fluid behavior in microchannels depends on fluid properties. Many applications use Newtonian liquids, while biofluids and
Applications span microfluidic labs-on-a-chip, chemical synthesis in microreactors, analytical devices, and cooling of microelectronics and electronics.
Key design considerations include pressure drop, thermal performance, chemical compatibility, and clogging or fouling due to
Performance metrics commonly used are pressure drop, Nusselt number for heat transfer, and a mixing or reaction