Numerical Study of Turbulent Channel Flow over Surfaces with Variable Spanwise Heterogeneities: Topographically-driven Secondary Flows Affect Outer-layer Similarity of Turbulent Length Scales
Sign Up to like & getrecommendations! Published in 2017 at "Flow, Turbulence and Combustion"
DOI: 10.1007/s10494-017-9839-5
Abstract: Wall-bounded turbulent flows over surfaces with spanwise heterogeneous surface roughness – that is, spanwise-adjacent patches of relatively high and low roughness – exhibit mean flow phenomena entirely different to what would otherwise exist in the… read more here.
Keywords: outer layer; channel; secondary flows; spanwise ... See more keywords
Optimization of the Spanwise Twist of a Flapping Wing for Bird-sized Aircraft using a Quasi-Steady Aerodynamic Model
Sign Up to like & getrecommendations! Published in 2019 at "International Journal of Aeronautical and Space Sciences"
DOI: 10.1007/s42405-019-00154-9
Abstract: This paper analyzes the effect of spanwise distribution of twist angle on the forces generated by flapping wings as well as the power requirements. We consider four sample profiles of the twist angle as a… read more here.
Keywords: flapping wing; twist; spanwise; optimization spanwise ... See more keywords
Flow and heat transfer characteristics in rectangular channels using combination of convex-dimples with grooves
Sign Up to like & getrecommendations! Published in 2017 at "Applied Thermal Engineering"
DOI: 10.1016/j.applthermaleng.2016.11.047
Abstract: Abstract In this paper, the main objective is to reveal the usefulness of placing convex dimples upstream of grooves on the improvement of the thermal performance and to address the effects of convex dimple spanwise… read more here.
Keywords: convex; convex dimples; convex dimple; heat transfer ... See more keywords
Flow characteristics of various three-dimensional rounded contour bumps in a Mach 1.3 freestream
Sign Up to like & getrecommendations! Published in 2017 at "Experimental Thermal and Fluid Science"
DOI: 10.1016/j.expthermflusci.2016.08.027
Abstract: Streamwise and spanwise flow pattern over three rounded contour bumps with different flow control strategies employed have been experimentally investigated in a Mach 1.3 freestream. Surface oil flow visualisation, Schlieren photography and particle image velocimetry… read more here.
Keywords: contour bumps; bump valley; rounded contour; mach freestream ... See more keywords
Spanwise flow development within a laminar separation bubble under natural and forced transition
Sign Up to like & getrecommendations! Published in 2018 at "Experimental Thermal and Fluid Science"
DOI: 10.1016/j.expthermflusci.2018.02.032
Abstract: Abstract The variation of streamwise and spanwise characteristic wavelengths of a NACA 0018 laminar separation bubble under natural and periodic excitation conditions is investigated experimentally. Periodic forcing is applied with an AC-DBD plasma actuator, and… read more here.
Keywords: separation bubble; bubble natural; excitation; spanwise ... See more keywords
Natural convection in a cubical cavity with a coaxial heated cylinder
Sign Up to like & getrecommendations! Published in 2018 at "International Journal of Heat and Mass Transfer"
DOI: 10.1016/j.ijheatmasstransfer.2017.11.046
Abstract: Abstract High-resolution three-dimensional simulations were conducted to investigate the velocity and temperature fields in a cold cubical cavity due to natural convection induced by a centrally placed hot cylinder. Unsteady, incompressible Navier-Stokes equations were solved… read more here.
Keywords: cavity; cylinder; spanwise; enclosure ... See more keywords
Reconsideration of spanwise rotating turbulent channel flows via resolvent analysis
Sign Up to like & getrecommendations! Published in 2018 at "Journal of Fluid Mechanics"
DOI: 10.1017/jfm.2018.894
Abstract: We study the effect of spanwise rotation in turbulent channel flow at both low and high Reynolds numbers by employing the resolvent formulation proposed by McKeon & Sharma (J. Fluid Mech., vol. 658, 2010, pp.… read more here.
Keywords: turbulent channel; analysis; rotation; across spectral ... See more keywords
Separation drag reduction through a spanwise oscillating pressure gradient
Sign Up to like & getrecommendations! Published in 2021 at "Journal of Fluid Mechanics"
DOI: 10.1017/jfm.2020.1124
Abstract: Abstract An oscillating spanwise pressure gradient is imposed numerically to control the flow separation and reduce the drag of a turbulent flow in a channel with square bars. The transverse flow produces a maximum drag… read more here.
Keywords: pressure gradient; power; spanwise; drag reduction ... See more keywords
Localizing effect of Langmuir circulations on small-scale turbulence in shallow water
Sign Up to like & getrecommendations! Published in 2020 at "Journal of Fluid Mechanics"
DOI: 10.1017/jfm.2020.215
Abstract: Wall-resolved and wall-modelled large-eddy simulations are performed to study the localizing effect of Langmuir cells (LCs) on small-scale background turbulence in shallow water. The total velocity fluctuations are decomposed into an LC content extracted by… read more here.
Keywords: langle rangle; water; turbulence; background turbulence ... See more keywords
Bifurcation and multiple states in plane Couette flow with spanwise rotation
Sign Up to like & getrecommendations! Published in 2021 at "Journal of Fluid Mechanics"
DOI: 10.1017/jfm.2021.45
Abstract: Abstract We present a derivation that begins with the Navier–Stokes equation and ends with a prediction of multiple statistically stable states identical to those observed in a spanwise rotating plane Couette flow. This derivation is… read more here.
Keywords: couette flow; plane couette; spanwise; multiple states ... See more keywords
Flow separation control over a rounded ramp with spanwise alternating wall actuation
Sign Up to like & getrecommendations! Published in 2019 at "Physics of Fluids"
DOI: 10.1063/1.5055948
Abstract: An implicit large-eddy simulation is carried out to study turbulent boundary-layer separation from a backward-facing rounded ramp with active wall actuation control. This method, called spanwise alternating distributed strips control, is imposed onto the flat… read more here.
Keywords: flow separation; control; rounded ramp; separation ... See more keywords