Viscoelastic Flows

MMany liquids in industry and biology are viscoelastic (like paints, blood, saliva, and DNA suspensions among many others), displaying a mixture of both viscous and elastic properties. These fluids are fundamental for a myriad of industrial processes (such as mixing of chemicals or cooling of microprocessors), however they are still not well understood due to the complexity of the mathematical models that describe them. The current consensus is that there are three “types” of viscoelastic chaos: modified Newtonian turbulence, elastic turbulence, and elasto-inertial turbulence.

We’ve identified a linear instability present in the arguably most popular viscoelastic model (FENE-P), and we have shown that this instability is capable of triggering chaotic dynamics with and without inertia. We’ve also studied the state-space of elasto-inertial turbulence, revealing that up to four different attractors (an arrowhead, a chaotic arrowhead, the laminar state, and elastoinertial turbulence) can be present for the same parameter regime.

We hope to better understand the origins of and the connections between the chaotic states in viscoelastic turbulence in this project.