Investigation of Marangoni-induced flows in vertical microchannels

Uğur, Ayşe
Marangoni convection is defined as the tendency of movement within a fluid from the regions of lower surface tension to those of higher locations. In literature, there are various studies related to Marangoni convection in horizontal microfluidic and microgravity systems. However, the researches about Marangoni convection in vertical flows for closed systems are relatively fewer in number. In this study, Marangoni effect due to temperature gradient is numerically investigated through a fluid-fluid interface in a vertical microchannel made of polydimethylsiloxane (PDMS). Marangoniinduced flow is created by forming an interface between air and water, due to Cassie- Baxter state observed in the hydrophobic surfaces. Firstly, a validation study is performed using experimental data in the literature for a horizontal setup. For various sizes of a vertical microchannel, Marangoni convection is numerically investigated to analyse flow characterization and its effect on temperature and velocity profiles.


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Citation Formats
A. Uğur, “Investigation of Marangoni-induced flows in vertical microchannels,” M.S. - Master of Science, Middle East Technical University, 2022.