Investigation of the interface behavior of a viscous fluid under free surface shear flow using an eccentric transparent Couette cell

Abstract In the present work, a prototype was developed to observe flow behavior of viscous fluids under free surface shear and determine an adhesion energy in this geometry. The geometry consists eccentric Couette cell (outer cylinder radius 89.5 mm, inner 43.75 mm minimal gap 3 mm) that can be used two modes, where both cylinders respectively rotate same or opposite directions. Cylinders are horizontal short relatively their diameters (30 long). Transparent windows allow in-situ observations. design, development, testing with model fluid (silicone 2.2 10 4 Pa.s Newtonian viscosity) reported paper. small volumes (fill factor smaller than 15%) investigated co- counter-rotating configurations steady-state conditions. Stationary conditions were identified mode. velocity resulting observations studied analysed. However, for silicone fluid, bulk dissipative is much larger work adhesive forces regimes. contribution could not detected fluid.