Session 1B: Inaugural Lectures by Fellows/Associates

Musti J Swamy

Complex fluids behavior at the interface: Beyond the trivialities

Complex fluids ranging from polymeric solutions, colloidal suspensions to bacterial suspensions are ubiquitous but their behavior at the solid-fluid interface are often distinctive. These distinctions will be highlighted in this talk through multiple interfacial phenomena. The journey will start with the dramatic climbing of certain viscoelastic fluids like polymeric solutions onto an immersed rotating rod. This classical effect, called the Weissenberg effect has been actively utilized in electrospinning, transporting of high viscosity solution at picolitre level and in fabrication of micro/nano structures. This phenomena will be revisited with a simple question‒does replacing the immersed rod with an oil-dipped rod alter the features of the rod-climbing effect? While the effect of shear on complex fluids is explored in the first part of this talk, the second part focuses on flow dynamics of polymeric fluid through cellulosic media in capillary rise experiments. Thereafter, we proceed to probe the response of another class of complex fluids, colloidal suspensions in discrete form, i.e., as droplets subjected to evaporation. In particular, we attempt to characterisethe evaporation via liquid cap evolution dynamics instead of the classical approach of evaporation modes.