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Showing 1 to 14 of 14 for “"Wall-bounded turbulent flows"”.
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Very -Large -Scale Motions in Wall -Bounded Turbulent Flows
… packets is a robust and significant feature of wall-bounded turbulence over a wide range of Reynolds numbers. The hairpin-vortex-packet model of turbulence provides a consistent explanation for the distribution of energy among the largest scales of the flow and underscores the importance of the …
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Pressure signature in adverse-pressure-gradient wall bounded turbulent flows
… to the recognition of universal patterns in wall-bounded adverse pressure gradient turbulent flows. For this purpose, the experimental work has been carried out towards further understanding of this class of flows, especially when the pressure gradient is increasingly adverse. Adverse …
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Control of the buffer and logarithmic layers in wall-bounded turbulent flows
… separately the buffer and logarithmic layers in wall-bounded turbulent flows. In the case of buffer-layer control, we examine the effect on near-wall turbulence of displacing the apparent, virtual origins perceived by different components of the overlying flow. This mechanism is commonly reported …
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New integral and differential computational procedures for incompressible wall-bounded turbulent flows
… presented for the simulation of incompressible wall-bounded turbulent flows. First, an integral method based on the strip integral method has been developed for the solution of three-dimensional turbulent boundary-layer flows. The integral equations written in a general form using non-orthogonal …
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Polymers and plastrons : active and passive drag reduction in wall-bounded turbulent flows
Frictional energy dissipation in wall-bounded turbulence is ubiquitous in modern engineering systems, ranging from the flow of liquids through pipelines, to the drag-inducing boundary layer around ships and submarines. The effective mitigation of this frictional drag is therefore of great practical …
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IMPLEMENTATION AND PERFORMANCE OF WALL MODELS FOR LARGE EDDY SIMULATION OF NON-EQUILIBRIUM TURBULENT BOUNDARY LAYERS
Accurate prediction of high-Reynolds-number wall-bounded turbulent flows is essential for the understanding and flow control of many engineering applications such as aircraft, turbomachinery, and marine vehicles. Additionally, most practical flows exhibit nonequilibrium effects such as pressure …
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Experiments on turbulent flows in rough pipes: spectral scaling laws and the spectral link
… the existence of a “spectral link” between the turbulent energy spectra and the attendant turbulent mean velocity profile in a pipe flow, we establish new scaling laws for the turbulent energy spectra of pipe flows. These new scaling laws— an inner scaling law and an outer scaling law—differ …
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Amplitude modulation of velocity and wall shear stress in turbulent channel flow with hemispherical roughness
"Near-wall turbulence cycles tend to be self-sustained in low Reynolds number wall-bounded turbulent flows. However, large-scale structures that reside in the outer region of the flow grow more energetic as Reynolds number increases and impart strong ""footprints"" on the near-wall turbulence. In …
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Experimental and Numerical Investigation of Turbulent Heat Transfer due to Rectangular Impinging Jets
… transfer and flow characteristics of rectangular turbulent impinging jets issued from a 24:1 aspect ratio and 24:1 contraction ratio nozzle were investigated experimentally and numerically. In the heat transfer measurements; a thin stainless-steel foil was utilized to obtain iso-flux boundary …
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Spectral modeling of an idealized atmospheric surface layer
… and ecosystem health. However, the ASL is turbulent, and therefore characterized by complex dynamics across a wide range of spatial and temporal scales. Explicitly modelling turbulent motions in the ASL at all scales is computationally expensive and beyond current capabilities. In this …
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The dynamics of the outer region of wall-bounded turbulence : La dinámica de la zona exterior en la turbulencia de pared
… analysis of the dynamics of the outer region of wall-bounded flows, focusing on the interaction between the inner- and outer- layers. The primary tool used in the present study is a set of Direct Numerical Simulations (DNS) of turbulent channels with friction Reynolds number Reτ ≈ 630. In those …
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Modeling transient multiphase flow and mold top surface behavior in steel continuous casting
… models to investigate transient multiphase turbulent flow physics in the mold region and mold top surface behavior during continuous casting of steel slabs. Each model can be used independently or combined together as a comprehensive system to gain insights into the inter-related multiphase …
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Multiphase Flow Dynamics in Confined Domains—A DNS Study of Bubbly, Thermal and Riblet-Induced Turbulence
… a comprehensive investigation of multiphase and wall-bounded turbulent flows using high-fidelity direct numerical simulations (DNS), with an emphasis on the fundamental mechanisms governing heat transfer, turbulence modulation, and instability-driven transition. By systematically studying three …
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Statistical Scaling of Turbulent Surface Pressure in the Atmospheric Boundary Layer
… fluctuations to be an interaction of the turbulent vertical velocity with the shear rate in the mean wind. In this work, the existing theoretical framework was extended to investigate the effects of atmospheric stability, shear anisotropy, and different turbulence models. A …