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The nonlocal nature of the Reynolds stress
Comptes Rendus. MécaniqueA nonlocal expression for the turbulent Reynolds stress $\overline{u^{\prime }v^{\prime }}$ solves in a unified manner for the velocity profiles in jets, shear layers, wakes, and boundary layers, offering predictions consistent with known measurements in
Villermaux, Emmanuel
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Coastal Engineering 1984, 1984 The on-offshore and the vertical components u, w of the velocity in a surf zone on a uniformly sloping beach in a wave tank were measured simultaneously with a laser-doppler velocimeter under two conditions. The time variation of the Reynolds stress -u'w' during one wave period is discussed.
T. Sakai, I. Sandanbata, M. Uchida
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Realizability of Reynolds-stress turbulence models [PDF]
The Physics of Fluids, 1977 It is shown that certain existing phenomenological models of turbulence in terms of differential equations for the Reynolds stresses Rαβ=〈u′α u′β〉 do not guarantee realizable solutions. The known realizability conditions are Rαβ⩾0 for α=β and Rαβ2⩾Rαα Rββ for α≠β. A stronger requirement is that the matrix Rαβ be positive semi-definite.
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Test problem of flow modelling in the Rotor 37 compressor stage
Авіаційно-космічна техніка та технологія, 2023 The subject of the study is the dependence of the degree of pressure increase on the airflow in the impeller of the axial compressor degree. The object of study is the Rotor 37 axial compressor.
Andrii Duliepov +4 more
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Distribution and motion characteristics of Q-events for open-channel uniform flow
Shui kexue jinzhan, 2016 To understand the time-averaged transient motion characteristics of Q-events for open-channel uniform flow (first-quadrant (Q1), second-quadrant(Q2), third-quadrant(Q3), fourth-quadrant(Q4)), a high-frequency particle image velocimetry system was used to
YANG Shengfa +4 more
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AIP Advances, 2022 To improve the prediction accuracy of separated flow based on the Reynolds Averaged Navier–Stokes model, the model constants of the baseline Reynolds stress model are calibrated by the ensemble Kalman filter data assimilation method.
Xiliang Song +3 more
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Numerical simulation of grid-generated turbulent particulate flow by three-dimensional Reynolds stress; pp. 161–174 [PDF]
Proceedings of the Estonian Academy of Sciences, 2013 A three-dimensional (3D) Reynolds stress turbulence model based on 3D Reynolds-averaged NavierâStokes equations has been elaborated for grid-generated turbulence in particulate downward flow arranged in the channel domain of the square cross section ...
Alexander Kartushinsky +6 more
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Journal of Fluid Science and Technology, 2023 In this study, the liquid film thickness of slug flow in a microchannel was numerically investigated. Particularly, we focused on a flow regime with high Reynolds and capillary numbers; these dimensionless number were independently modified to ...
Daisuke TSUNEOKA, Junnosuke OKAJIMA
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Assessment of Reynolds-stress models for aeronautical applications
International Journal of Heat and Fluid Flow, 2022 Three Reynolds-Stress Models (RSMs) have been benchmarked on industrial configurations with aeronautical applications. The models are first compared on a zero-pressure-gradient boundary layer, which highlights the differences in the near-wall approaches of the models. Results are then analyzed for the Skåre & Krogstad adverse-pressure-gradient boundary
Sporschill, Gustave +4 more
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Intense Reynolds-stress events in turbulent ducts
International Journal of Heat and Fluid Flow, 2021 Abstract The aim of the present work is to investigate the role of intense Reynolds shear-stress events in the generation of the secondary flow in turbulent ducts. We consider the connected regions of flow where the product of the instantaneous fluctuations of two velocity components is higher than a threshold based on the long-time turbulence ...
Atzori M. +3 more
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