Hydrodynamic interactions between viscoelastic fluid and biomimetic cilia-like structures

In this research, we explore the mechanisms underlying the emergence of waves and elastic turbulence in a viscoelastic flow around a micropillar array that mimics ciliary structure. Recent investigations in our research group have uncovered intriguing wave patterns within the regime of canopy elastic turbulence. These wave patterns manifest within the viscoelastic fluids as they flow through microchannels containing micropillar arrays, closely mimicking ciliary structures. However, the origin of the wave patterns is still not well understood. Here we employed micro-particle imaging velocimetry (µ-PIV) and flow-induced birefringence to examine how the rheological properties of the fluid and geometric features of the ciliary structures, such as the number and density, affect the flow dynamics and the characteristics of wave patterns. This work could enhance knowledge of natural ciliary systems and microscale fluid-structure interactions.