Moving Contact Lines Over Imperfect Surfaces: From Stick-Slip to Steady-Sliding

Explore the complex dynamics of fluid-fluid interfaces moving over heterogeneous solid surfaces in this 48-minute lecture by Dr. Bauyrzhan Primkulov from the Massachusetts Institute of Technology. Delve into the fascinating world of contact line motion, from the behavior of raindrops on window glass to the broader implications for fluid mechanics. Examine how surface defects influence fluid behavior, leading to phenomena such as pinning, stick-slip motion, and steady sliding. Learn about the reduction of partial wetting displacement dynamics to a system of coupled ordinary differential equations, simplifying the complexity of stick-slip dynamics to key parameters. Discover the mechanical analog that elucidates both constant-force and constant-rate displacement regimes. Investigate the crossover from stick-slip motion to steady sliding at high displacement rates, and understand the balance of timescales that rationalizes recent experimental observations. Gain insights into this elegant physics problem with wide-ranging practical applications in fluid mechanics.