Investigation of the flow dynamics in a channel constricted by periodic hills
TypeCommunications avec actes
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.
Showing items related by title, author, creator and subject.
GLOERFELT, Xavier; CINNELLA, Paola (Springer Science and Business Media LLC, 2019-03-14)Large eddy simulations are carried out for flows in a channel with streamwise-periodic constrictions, a well-documented benchmark case to study turbulent flow separation from a curved surface. Resolution criteria such as ...
SCIACOVELLI, Lucas; CINNELLA, Paola; GLOERFELT, Xavier (Cambridge University Press (CUP), 2017-05-19)The influence of dense-gas effects on compressible wall-bounded turbulence is investigated by means of direct numerical simulations of supersonic turbulent channel flows. Results are obtained for PP11, a heavy fluorocarbon ...
BUFI, Elio A.; CINNELLA, Paola; MERLE, Xavier; CINNELLA, Paola (ASME, 2015-06-15)The design of an efficient organic rankine cycle (ORC) expander needs to take properly into account strong real gas effects that may occur in given ranges of operating conditions, which can also be highly variable. In this ...
MERLE, Xavier; CINNELLA, Paola (Elsevier, 2015)A Bayesian inference methodology is developed for calibrating complex equations of state used in numerical fluid flow solvers. Precisely, the input parameters of three equations of state commonly used for modeling the ...
MERLE, Xavier; CINNELLA, Paola (Elsevier, 2014)A Bayesian inference methodology is developed for calibrating complex equations of state used in numerical fluid flow solvers. Precisely, the input parameters of three equations of state commonly used for modeling the ...