Contact line dynamics in curtain coating of non-Newtonian liquids
نویسندگان
چکیده
The rheological characteristics of liquids play an important role in the flow near dynamic contact lines, where deformation rates are extremely large. liquid line dynamics and free surface configuration curtain coating polymer solutions were experimentally studied using visualization to determine effect two characteristics: shear thinning extensional thickening. critical web speeds for heel formation, on moving substrate shifts upstream falling curtain, air entrainment, downstream bubbles appear, determined over a range rates. conditions compared behavior observed Newtonian liquid. Moreover, described by three dimensionless parameters: Deborah number, Ohnesorge ratio speed velocity at line.
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ژورنال
عنوان ژورنال: Physics of Fluids
سال: 2021
ISSN: ['1527-2435', '1089-7666', '1070-6631']
DOI: https://doi.org/10.1063/5.0064467