(365k) Understanding Nanoscale Slip through the Lens of Taylor-Aris Dispersion

In a nanofluidic device, the presence of hydrodynamic slip at the fluid-solid interface allows researchers to create surfaces with little to no resistance to fluid flow. Fluid slip plays an important role in fast mass transport in nanoscale devices when the confining length scale is comparable to the molecular size of the fluid particles, and has various applications in water filtration, drug delivery, and lap-on-chip devices.

Hydrodynamic slip is inherently a microscopic phenomenon, but fluid slippage at a solid boundary can be incorporated into the Navier-Stokes description of the system by using an appropriate slip boundary condition. Previous literature has studied the underlying microscopic mechanisms that affect slip, in this work we explore the possibility of reproducing the molecular-scale behavior of slip from Taylor-Aris dispersion. We model fluid slip velocity in a plane Couette flow in terms of the shear-augmented and equilibrium self-diffusivities of the fluid. By conducting extensive molecular dynamics (MD) simulations of monomeric and polymeric fluids at various thermodynamic and geometric conditions, we show that slip velocity measured directly from particle velocities is essentially recovered from that measured via Taylor-Aris dispersion. Our work demonstrates that an interfacial quantity like slip velocity has a signature hidden inside bulk fluid properties like self-diffusivities in the streamwise and spanwise directions.

Research Interests:

I am a chemical engineer interested in the modeling and simulation of transport processes with applications in the energy sector, carbon capture, and nanotechnology. Throughout my research journey, I have worked on projects like investigating nanoscale fluid slippage through molecular dynamics, designing a new generation of plastic composites for better recyclability, computationally modeling microreactors to study mixing of reactant/product gases, designing topologically optimized absorber columns for carbon capture and synthesizing carbon-supported Platinum catalysts for fuel cells.

These experiences have fostered my development as an independent thinker and have deepened my understanding of how different engineering systems can be made more sustainable and energy-efficient. My work has spanned system sizes all the way from several meters (absorber columns) down to the molecular scale (nanofluidic systems), thus, helping me build expertise in continuum-scale as well as molecular-scale simulations and modeling. Coupled with my experience in process optimization, I wish to apply my learnings to further explore how molecular properties can have macro-scale implications on the energy efficiency and overall performance of a system. A brief outline of my professional experience can be found at this link to my CV