Investigation of the flow dynamics in a channel constricted by periodic hills
Communication avec acte
Abstract
The present study aims at getting better insight of the complex flow dynamics in a channel constricted by periodic hills. This is a popular test case ofer used to assess LES and RANS/LES models, which appears as a compendium of flow separation and reattachment from a curved boundary, generation of an unsteady shear layer surrounding the recirculation bubble, strong acceleration on the convex windward wall of the next hill, attached boundary layer on the ceiling subject to intense instantaneous pressure gradients, recycling of the turbulence due to the periodicity assumption. One unresolved issue which is addressed in the present work concerns the early birth of the shear layer and the rapid eruption of large scales, with a characteristic length-scale many times greater than the thickness of the initial shear. The mechanism leading to large vortices in the shear layer indeed bears similarities with the collective interaction phenomenon, which has been encountered for mixing layer excited by a low-frequency component. The present results are a first attempt to characterize this complex process highly disrupted by the turbulent fluctuations turning into the periodic box.
Files in this item
Collections
Related items
Showing items related by title, author, creator and subject.
-
Sparse Bayesian Learning of Explicit Algebraic Reynolds-Stress models for turbulent separated flows Article dans une revue avec comité de lectureA novel Sparse Bayesian Learning (SBL) framework is introduced for generating parsimonious stochastic algebraic stress closures for the Reynolds-Averaged Navier–Stokes (RANS) equations from high-fidelity data. The models ...
-
Article dans une revue avec comité de lectureGLOERFELT, Xavier; ROBINET, Jean-Christophe; SCIACOVELLI, Luca; CINNELLA, Paola; GRASSO, Francesco (Cambridge University Press (CUP), 2020)A study of dense-gas effects on the stability of compressible boundary-layer flows is conducted. From the laminar similarity solution, the temperature variations are small due to the high specific heat of dense gases, ...
-
Article dans une revue avec comité de lectureSCIACOVELLI, Luca; GLOERFELT, Xavier; PASSIATORE, Donatella; CINNELLA, Paola; GRASSO, Francesco (Springer, 2020-03)High-speed turbulent boundary layers of a dense gas (PP11) and a perfect gas (air) over flat plates are investigated by means of direct numerical simulations and large eddy simulations. The thermodynamic conditions of the ...
-
Large eddy simulation of turbomachinery flows using a high-order implicit residual smoothing scheme Article dans une revue avec comité de lectureHOARAU, Jean-Christophe; CINNELLA, Paola; GLOERFELT, Xavier (Elsevier, 2020)A recently developed fourth-order accurate implicit residual smoothing scheme (IRS4) is investigated for the large eddy simulation of turbomachinery flows, characterized by moderate to high Reynolds numbers and subject to ...
-
Article dans une revue avec comité de lectureSCIACOVELLI, Luca; CINNELLA, Paola; GLOERFELT, Xavier (Springer Verlag (Germany), 2018)Dense gas effects, encountered in many engineering applications, lead to unconventional variations of the thermodynamic and transport properties in the supersonic flow regime, which in turn are responsible for considerable ...