Harnessing Deformation in Soft Microfluidics

Abstract: Soft microfluidics offers opportunities for flow control that have no direct analogue in rigid microfluidic systems. When the boundaries of a conduit deform in response to the fluid pressure, the resulting change in geometry modifies the hydraulic resistance and, in turn, the flow itself. This feedback can produce strongly nonlinear behaviour, but can also provide a route towards simple, autonomous microfluidic functionality.

In this talk, I will explore this interplay between fluid flow and structural deformation through two compliant microfluidic systems. In the first, a channel with a highly deformable wall can undergo substantial changes in cross-section, giving rise to a nonlinear and non-monotonic relationship between pressure drop and flow rate. In the second, flow through a channel embedded within a confined soft solid causes deformation that progressively constricts the conduit. The resulting feedback produces a limiting flow rate under pressure-controlled conditions and a fuse-like choking response when the flow rate is imposed.

Together, these examples illustrate how understanding the fundamental mechanics of flows through deformable conduits can reveal unexpected transport phenomena and suggest new principles for designing passive components in soft microfluidic circuits.

Bio: Draga Pihler-Puzović is a Reader in Physics at the University of Manchester. Her research lies at the interface of fluid mechanics, solid mechanics, soft matter and nonlinear dynamics, with a particular focus on transport and deformation in soft and compliant systems. She combines experiments, theory and numerical simulations to uncover the fundamental physics underpinning phenomena ranging from physiological processes to industrially motivated applications.