Physical Review Fluids
Author(s): Wu-Yang Zhang, Wei-Xi Huang, and Chun-Xiao Xu
Numerical simulations of turbulent flows over traveling wavy boundaries reveal that very large-scale motions are enhanced by a wavy boundary, but their intensities are decreased as wave phase speed increases. The wave-induced flow provides an extra energy transfer for the very-large-scale motions.
[Phys. Rev. Fluids 4, 054601] Published Tue May 07, 2019
Author(s): Aaron Rips and Rajat Mittal
Flow-induced flutter of flexible flapping membranes can greatly increase scalar mixing in channel flows in the inertial microfluidics regime. We use flow-structure interaction simulations to investigate their flow physics and mixing ability and find rapid mixing with relatively low pressure loss.
[Phys. Rev. Fluids 4, 054501] Published Mon May 06, 2019
Author(s): Kevin Rosenberg, Sean Symon, and Beverley J. McKeon
The representation of self-sustaining processes via resolvent analysis for turbulent flows is improved where the resolvent operator is not low rank by approximating the nonlinear forcing using parasitic modes, with analogy to weakly nonlinear analysis near critical Reynolds numbers.
[Phys. Rev. Fluids 4, 052601(R)] Published Wed May 01, 2019
Author(s): Martin Magill, Aaron Coutino, Benjamin A. Storer, Marek Stastna, and Francis J. Poulin
Vortices in a model of the solar tachocline decay into pairs of stable donutlike Alfvén waves. These propagate zonally in opposite directions, colliding periodically. Nonlinear effects distort the waves significantly after each collision, but between collisions their shapes and speed remain fixed.
[Phys. Rev. Fluids 4, 053701] Published Wed May 01, 2019