# New Papers in Fluid Mechanics

### Near-wall streamwise turbulence intensity as ${\text{Re}}_{τ}→∞$

Author(s): Yongyun Hwang

Two possible and physically meaningful scalings for near-wall streamwise turbulence intensity are derived using velocity spectra. First, if viscous wall effect on the wall-attached inactive motions from the log and outer layers is negligible enough so that the related spectrum does not diminish with Reynolds number, the near-wall turbulence intensity grows indefinitely and scales as ln Reτ. Whereas if it is strong enough so that the near-wall turbulence intensity remains finite at all Reynolds numbers, it scales as 1/ln Reτ. The existing measurement data favors the latter scaling, but the issue will be settled by the availability of such data at higher Reynolds numbers.

[Phys. Rev. Fluids 9, 044601] Published Tue Apr 02, 2024

### Connecting finite-time Lyapunov exponents with supersaturation and droplet dynamics in a turbulent bulk flow

Author(s): Vladyslav Pushenko and Jörg Schumacher

The impact of turbulent mixing on an ensemble of initially monodisperse water droplets is studied in a turbulent bulk that serves as a simplified setup for the interior of a turbulent ice-free cloud. A mixing model was implemented that summarizes the balance equations of water vapor mixing ratio and…

[Phys. Rev. E 109, 045101] Published Mon Apr 01, 2024

### Cuboid drop: A low-dimensional model of drop dynamics on a substrate

Author(s): Tristan Gilet

The dynamics of a liquid drop attached to a solid and subjected to arbitrary accelerations can be qualitatively reproduced with a low-dimensional model in which the drop is replaced by a cuboid. The cuboid deforms, vibrates and slides similarly to a drop, while being much simpler to describe mathematically.

[Phys. Rev. Fluids 9, 043601] Published Mon Apr 01, 2024