Large-eddy simulations of the flow on an aerofoil with leading-edge imperfections

We performed large-eddy simulations of the flow over an aerofoil to understand the effects of leading-edge roughness designed to mimic ice accretion. The roughness elements protrude outside the boundary layer, which, near the leading edge, is very thin; thus, the configuration does not represent a c...

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Detalles Bibliográficos
Autores: Kumar, Vishal, Piomelli, Ugo, Lehmkuhl Barba, Oriol|||0000-0002-2670-1871
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/351570
Acceso en línea:https://hdl.handle.net/2117/351570
https://dx.doi.org/10.1080/14685248.2021.1973015
Access Level:acceso abierto
Palabra clave:Computer simulation
Leading edges (Aerodynamics)
Ice accretion
Turbulence--Simulation methods
Large-eddy simulations
Aerofoil
Roughness
Icing
Simulació per ordinador
Àrees temàtiques de la UPC::Informàtica::Aplicacions de la informàtica::Aplicacions informàtiques a la física i l‘enginyeria
Descripción
Sumario:We performed large-eddy simulations of the flow over an aerofoil to understand the effects of leading-edge roughness designed to mimic ice accretion. The roughness elements protrude outside the boundary layer, which, near the leading edge, is very thin; thus, the configuration does not represent a classical rough-wall boundary layer, but rather the flow over macroscopic obstacles. A grid convergence study is conducted and results are validated by comparison to numerical and experimental studies in the literature. The main effect of the obstacles is to accelerate transition to turbulence. Significant variations in structure generation are observed for different roughness shapes. The three-dimensionality of the irregularities has a strong impact on the flow: it creates alternating regions of high-speed (‘peaks’) and low-speed (‘valleys’) regions, a phenomenon termed ‘channelling’. The valley regions resemble a decelerating boundary layer: they exhibit considerable wake and higher levels of Reynolds stresses. The peak regions, on the other hand, are more similar to an accelerating one. Implications of the channelling phenomenon on turbulence modelling are discussed.