Passive stabilization of crossflow instabilities by a reverse lift-up effect
Abstract
A novel mechanism is identified, through which a spanwise-invariant surface feature (a two-dimensional forward-facing step) significantly stabilizes the stationary crossflow instability of a three-dimensional boundary layer. The mechanism is termed here as reverse lift-up effect, inasmuch as it acts reversely to the classic lift-up effect; that is, kinetic energy of an already existing shear-flow instability is transferred to the underlying laminar flow through the action of cross-stream perturbations. To characterize corresponding energy-transfer mechanisms, a theoretical framework is presented, which is applicable to generic three-dimensional flows and surface features of arbitrary shape with one invariant spatial direction. The identification of a passive geometry-induced effect responsible for dampening stationary crossflow vortices is a promising finding for Laminar Flow Control applications.
Keywords
Cite
@article{arxiv.2310.03189,
title = {Passive stabilization of crossflow instabilities by a reverse lift-up effect},
author = {Jordi Casacuberta and Stefan Hickel and Marios Kotsonis},
journal= {arXiv preprint arXiv:2310.03189},
year = {2023}
}
Comments
It contains 20 pages and 10 figures