Scaling laws are a useful way to characterize fluid flow over a wide range of flow rates and experimental conditions. Theorists now explain several earlier experiments by finding a scaling law that describes how a liquid-liquid interface changes shape when driven by viscous forces.
High-intensity x-ray measurements show how suspended particles in a narrow channel are attracted to—or repelled from—the channel walls depending on the ionic concentration of the suspension. These results could have implications for the design of nanofluidic devices.
A shear force can melt a colloidal glass, causing it to flow in a highly nonlinear fashion. Physicists have now found a way to put the description of this type of flow on a more formal theoretical footing.
Phys. Rev. Focus21, 2 (2008) – Published January 15, 2008
A pair of colliding water droplets merges on the rebound, rather than when they’re squeezing against each other. The results should improve understanding of the separation process of oil-water mixtures important in industry.