2025/01/14 by Andrzej Herczyński, Maciej Lisicki, Herczyński, Andrzej +1 · 2 voices
Engineering · #Aerosol Filtration and Electrostatic Precipitation #Fluid Dynamics and Thin Films
paper · pdf · doi:10.1063/5.0263624
Manipulation of viscous liquids is an essential kitchen activity—from pouring golden sirup onto a pancake to decorating a cake with whipped cream frosting or dispensing molten chocolate onto a strawberry. Typical viscosities in these and many other culinary flows, and the heights from which the streams are dispensed, make such jets susceptible to coiling instability. Indeed, the coiling of a thin thread of poured maple sirup is a source of fascination for children and adults alike, whereas the folding of the stream of ketchup squeezed out from a plastic bottle is a phenomenon familiar to all. In this paper, we review the fluid dynamics of such culinary flows and discuss separately the case when the substrate is stationary (honey on toast) and when it translates (cookies on a conveyor belt) or rotates (a pancake on a spinning hot plate). We also bring together and provide a unifying view of all scaling laws for the coiling frequency and radius and supply new scaling laws for the corresponding kinetic energy of the falling stream. It is hoped that this may encourage experimentation and enjoyment of physics in the kitchen and perhaps even lead to more elegant, if not more tasty, culinary results.