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Showing 1 to 12 of 12 for “"viscous sublayer"”.
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Riblets in the viscous sublayer : Optimal Shape Design of Microstructures
… assume that these microstructures remain in the viscous sublayer where the flow equations are the 3D incompressible, steady state Navier-Stokes equations with a Couette in- and outflow determinated through two boundary conditions, the no-slip condition on the lower boundary and the friction …
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Experimental analysis of flow and turbulence characteristics in oscillatory boundary layers from LDV measurements
… inside the boundary layer and even inside the viscous sublayer in some cases. A special set-up was built involving two LDV probes and a refraction-correcting device to be able to measure all three velocity components (u, v, w) simultaneously. From the velocity measurements, flow characteristics …
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The Velocity-Concentration Relationship in Turbulent Mass Transfer to a Wall
… layer is completely contained within the viscous sublayer.
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Turbulent Boundary Layer over a Piezoelectrically Excited Traveling Wave Surface
… boundary layer is pushed off the wall, and the viscous sublayer is thickened, indicating a reduction in shear stress. Analysis of the boundary layer at positions phase-locked to the wave oscillation suggests that the traveling waves induce a phase-lag effect in the flow. This phase-lag produces …
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Studies of the Interaction Between Drag-Reducing Polymers and a Turbulent Flow Field Using Pulsed Image Velocimetry and FENE Bead-Spring Model
… the viscosity in the buffer zone but not in the viscous sublayer. This increase in the viscosity results in damping of small eddies and an increase in the thickness of the buffer layer and reducing the drag.
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Effects of boundary roughness on turbulence in uniform open channel flow
… only in the near wall region but also within the viscous sublayer. Using the data from both the log law and linear viscous sublayer fits allowed for more reliable computations of shear stresses as well as a better understanding of how turbulence behaves over the full range of the flow. Previous …
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An Experimental Study of Turbulent Boundary Layers Subjected to High Free-stream Turbulence Effects
… friction coefficient (Cf) was deduced from the viscous sublayer. The difference between the U_tau obtained in the viscous sublayer mean velocity profile and the U_tau obtained in the semi-log layer was 1.5%. The skin friction coefficient was determined to increase by 10.5% when the …
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Studies of the Wall Shear Stress in a Turbulent Pulsating Pipe Flow
… and the turbulence fluctuations in the viscous sublayer, which is not described by present theories of turbulence.
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Stability, LES, and Resolvent Analysis of Thermally Non-uniform Supersonic Jet Noise
… generation). Wall models are used to capture the viscous sublayer at the nozzle. The Ffowcs Williams-Hawkings (FW-H) method is used for far-field noise predictions for all cases. Three-dimensionality is studied to investigate how injection in the shear layer acts to create a rotational inviscid …
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Passive Flow Control with Shark Skin and the Relevance of Low Speed Streaks to Denticle Actuation
… due an increase in the thickness of the viscous sublayer [9], and shear stress reduction due to the decrease of cross-flow fluctuation [10] underlying the hydrodynamics of fast-swimming sharks and providing insight for potential biomimetic designs that can utilize the same passive flow …
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Measurements of the Tip-gap Turbulent Flow Structure in a Low-speed Compressor Cascade
… skin friction velocity was measured by using viscous sublayer velocity profiles, which verified the presence of an intense lateral shear layer that was observed from surface oil flow visualizations. All second- and third-order turbulence quantities were measured to provide detailed data for …
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Near Wall Investigation of Three Dimensional Turbulent Boundary Layers
This report documents the experimental study for four different three-dimensional turbulent flows. The investigation focuses on near wall measurements in these flows. Several experimental techniques are used in the studies; however, the bulk of the investigation focuses on a …