Flow field disturbance due to point viscosity variations in a heterogeneous fluid

Abstract

A fluid can be heterogeneous in either its density or viscosity - its two basic material properties. In this Letter, we ask how an ambient flow field is disturbed due to a point viscosity variation in the fluid. If we are able to answer this question, we can create an arbitrary spatial distribution of viscosity discretely by placing viscosity sources and sinks of appropriate strength, allowing us to model complex fluids. As an example, we show how the hydrodynamics of a rigid particle is altered due to the presence of point viscosity variations.