Zhongzheng Wang

An interferometry method for confined 2D binary droplets in a humidity-controlled environment enables high-res measurement of drying kinetics and internal concentration fields to characterize drying and transport in complex fluids. Editors' suggestion: go.aps.org/4unsCpq

A simple tilt can drastically change the behavior of a liquid thread on a wire. Adjusting the angle of the wire at a fixed flow rate causes transitions from Rayleigh-Plateau to droplet drop-off, showing how geometry alone tunes the instability. go.aps.org/47z7928

Fog on a window after a breath mostly evaporates, but some tiny droplets remain. Experiments show that larger droplets grow as smaller ones shrink, following classic Ostwald ripening. A mean field model accurately predicts these dynamics. Read the Letter: go.aps.org/42mhr40

How can machine learning in fluid dynamics deepen our understanding of flow physics and expand its applications? A new perspective article explores key challenges and highlights the importance of open datasets, open-source tools, and training. Read more: go.aps.org/46rmPEb

📢 PRFluids Editors' suggestion: Gel-like skins that form on drying porous materials delay evaporation. By accounting for pore size gradients and viscosity-dependent vapor pressure, a new model predicts the evaporation slowdown observed in experiments. go.aps.org/4n7U9qR

Contact line dynamics in capillary tubes are notoriously hard to model. A phase-field approach with a novel formulation of boundary wetting conditions captures equilibrium states, wetting transitions, thin films, and pinch-off events, matching experiments. go.aps.org/3VEzvCu

A new constitutive law for viscous stresses in two-phase flows, derived from continuum mechanics and interface conditions, accurately captures experimental observations of exchange flows in a pipe and outperforms traditional ad-hoc models. Read more at go.aps.org/4lX9ES1

📢 PRFluids Editors' suggestion: How does a droplet split between two fibers? At specific angles, near-complete transfer from one fiber to the other is possible, highlighting how soft metamaterials can be harnessed to control liquid transport. Read more at go.aps.org/40jYON0

Solute transport in porous media is often modeled with constant dispersivity, but is this valid for shear-thinning fluids? Al-Qenae et al. show that the viscosity varies across pore spaces, enhancing dispersion, and present a model that accounts for it 🔗 go.aps.org/45IH15F

Immiscible fluid interfaces destabilize during invasion in porous media. Brodin et al. use 3D imaging to show that, depending on flow rate, the interface transitions from stable sheets to unstable fingers, bridging 2D theory with complex 3D behavior. 🔗 go.aps.org/4ekidTX

🗓️✏️ From the April issue (1) go.aps.org/4314L21 (2) go.aps.org/3RJMb9i (3) go.aps.org/3EJryXY (4) go.aps.org/4cXPtiN 
 Have a look at the full issue from the last month here go.aps.org/4jSpj3m #fluiddynamics

📢 PRFluids Editors' suggestion: How does oil get trapped in microscale pores during water invasion? McBride et al. show that higher oil viscosity and water speed cause more trapping, due to a transition from meniscus displacement to viscous fingering. 🔗 go.aps.org/4lXHp61

When active droplets squeeze through increasingly narrow microchannels, their shape changes from spherical to capsule-like, and the hydrodynamic signature shifts from symmetric, quadrupolar to an asymmetric velocity field. More, by Guchhait et al., at go.aps.org/42qjAeb

Clarke and Woods will discuss their paper, “Experiments on buoyancy-driven instability ahead of a dissolution front in a porous rock” (go.aps.org/4bT8mmG) at the PR Fluids Journal Club on Monday, March 31 (3pm GMT, 10am ET, 7am PT). Register here: go.aps.org/4iPRzTW