Results 11 to 20 of about 45,328 (229)

A vorticity-based criterion to characterise leading edge dynamic stall onset

Journal of Fluid Mechanics, 2022
We propose a more conservative, physically-intuitive criterion, namely, the boundary enstrophy flux ($BEF$), to characterise leading-edge-type dynamic stall onset in incompressible flows.
S. Sudharsan, B. Ganapathysubramanian, A. Sharma   +2 more
semanticscholar   +1 more source

Criteria for dynamic stall onset and vortex shedding in low-Reynolds-number flows [PDF]

Journal of Fluid Mechanics
Dynamic stall at low Reynolds numbers, $Re \sim O(10^4)$, exhibits complex flow physics with co-existing laminar, transitional and turbulent flow regions.
S. Sudharsan, Anupam Sharma
semanticscholar   +1 more source

Bifurcation scenario for a two-dimensional static airfoil exhibiting trailing edge stall

Journal of Fluid Mechanics, 2021
We numerically investigate stalling flow around a static airfoil at high Reynolds numbers using the Reynolds-averaged Navier–Stokes equations (RANS) closed with the Spalart–Allmaras turbulence model.
Denis Busquet, O. Marquet, F. Richez, M. Juniper, D. Sipp   +4 more
semanticscholar   +1 more source

Construction of reduced-order models for fluid flows using deep feedforward neural networks [PDF]

Journal of Fluid Mechanics, 2019
We present a numerical methodology for construction of reduced-order models (ROMs) of fluid flows through the combination of flow modal decomposition and regression analysis.
Hugo F. S. Lui, W. Wolf
semanticscholar   +1 more source

An Explanation for the Existence of Stall Hysteresis

Fluid Mechanics
An explanation of the mechanism for the difference in angle for separation and reattachment during stall on airfoils via potential flow and stall-prediction theories is proposed as follows: the reattachment angle of any given airfoil is the stall angle ...
Wallace Ii
semanticscholar   +1 more source

Trajectory optimization of a flapping-wing robot in a wind field

工程科学学报
Owing to wave obstruction, the speed of the horizontal wind field decreases as it approaches the sea surface. Consequently, the wind field that increases with height is referred to as a gradient wind field.
Xiaoyang WU, Zhiguo ZHANG, Wei HE, Jingyan QIN, Junhai ZHANG, Tingting MENG   +5 more
doaj   +1 more source

Link between subsonic stall and transonic buffet on swept and unswept wings: from global stability analysis to nonlinear dynamics

Journal of Fluid Mechanics, 2020
This paper examines the three-dimensional cellular patterns appearing on wings in subsonic stall and transonic buffet conditions. Unsteady Reynolds-averaged Navier–Stokes simulations are carried out for three-dimensional infinite swept configurations ...
Frédéric Plante, J. Dandois, Samir Beneddine, E. Laurendeau, D. Sipp   +4 more
semanticscholar   +1 more source

Cluster-based feedback control of turbulent post-stall separated flows [PDF]

Journal of Fluid Mechanics, 2018
We propose a cluster-based control strategy for feedback control of post-stall separated flows over an airfoil. The present approach partitions the flow trajectories (force measurements) into clusters, which correspond to characteristic coarse-grained ...
Aditya G. Nair, C. Yeh, E. Kaiser, B. R. Noack, S. Brunton, K. Taira   +5 more
semanticscholar   +1 more source

Shape‐Morphing Nanoengineered Hydrogel Ribbons as Hemostats

Advanced Functional Materials, EarlyView.
This study introduces a self‐assembling, shape‐morphing nanoengineered hydrogel ribbon system that rapidly forms porous aggregates in situ for efficient hemostasis in trauma and surgical applications. Abstract Rapid and effective hemorrhage control remains a major challenge in trauma and surgical care, particularly for complex or noncompressible wounds.
Ryan Davis Jr, Saptarshi Biswas, Jacob Aragon, Asaf Dana, Jasmine Sureka, Vaaridhi Ramanuja, Jeevika Thazhaiselvam, Sarah E. Miller, Taylor H. Ware, Akhilesh K. Gaharwar   +9 more
wiley   +1 more source

Numerical investigation of the effect of airfoil thickness on onset of dynamic stall [PDF]

Journal of Fluid Mechanics, 2017
Effect of airfoil thickness on onset of dynamic stall is investigated using large eddy simulations at chord-based Reynolds number of 200 000. Four symmetric NACA airfoils of thickness-to-chord ratios of 9 %, 12 %, 15 % and 18 % are studied.
Anupam Sharma, M. Visbal
semanticscholar   +1 more source