Characterisation of liquid film in a microstructured falling film reactor using laser scanning confocal microscopy

Flow pattern and break-up of liquid film in single-channel falling film microreactors

“…But for a shallow microchannel, the gas-liquid-solid three-phase contact line could locate right on the top of the side wall when the liquid flow rate was comparatively high, which caused to be larger than  (Fig. 9) [15,22]. As the liquid flow rate was decreased, the force balance on the liquid film could be maintained by deforming the interface profile towards the bottom of microchannel while still keeping the three contact line locate on the top of the side wall.…”

“…MWF for traditional falling film depends on the properties of fluid and solid surface. Due to the combination of capillary forces and micron-sized channel geometry, the gas-liquid interface inside microchannels was observed to be meniscus instead of being flat [15]. The thinnest part of liquid film was located in the middle of microchannel bottom.…”

“…As the second flow pattern occurs, the dry strip was partly wetted by the liquid film and formed dry patches. The third one displays as a complete falling film with the interface profile taking a form of flowing meniscus due to the capillary effect [15].…”

Determination of Liquid Film Thickness Following Draining of Contactors, Vessels, and Pipes in the Mcu Process

“…9 Fluid viscosity was 0.34 -2.3 cp, which is close to the viscosity of the liquids in the MCU process (1 -4 cp). Surface tension was 14 -23 dynes/cm, which is lower than the surface tension of the liquids in the MCU process (24 -59 dynes/cm).…”

Separation Units

“…The microchannels prevent break-up of the liquid film at low flow rates. Due to the combination of capillary forces and small channel widths, liquid being pulled up along the sides of the channels takes up a significant portion of the channel width and the surface of the liquid film assumes the form of a flowing meniscus [31].…”