• français
    • English
    français
  • Login
Help
View Item 
  •   Home
  • Dynamique des Fluides (DynFluid)
  • View Item
  • Home
  • Dynamique des Fluides (DynFluid)
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

Numerical Study of the Effect of Freestream Turbulence on by-pass Transition in a Boundary Layer

Article dans une revue avec comité de lecture
Author
CHERUBINI, Stefania
134975 Laboratoire de Dynamique des Fluides [DynFluid]
ROBINET, Jean-Christophe
134975 Laboratoire de Dynamique des Fluides [DynFluid]
DE PALMA, Pietro
19097 Dipartimento di Ingegneria Meccanica e Gestionale [DIMEG]

URI
http://hdl.handle.net/10985/9011
DOI
10.1016/j.egypro.2014.01.062
Date
2014
Journal
Energy Procedia

Abstract

We use direct numerical simulations in the presence of free-stream turbulence having different values of intensity, T u, and integral length scale, L, in order to determine which kind of structures are involved in the path to transition of a boundary-layer flow. The main aim is to determine under which conditions the path to transition involves structures similar to the linear or non-linear optimal perturbations. For high values of T u and L, we observe a large-amplitude path to transition characterized by localized vortical structures and patches of high- and low-momentum fluctuations. Such a scenario is found to correlate well with the L and hairpin structures resulting from the time evolution of non-linear optimal perturbations, whereas, for lower T u and L, a larger correlation is found with respect to linear optimal disturbances. This indicates that a large-amplitude path to transition exists, different from the one characterized by elongated streaks undergoing secondary instability. To distinguish between the two transition scenarios, a simple parameter linked to the streamwise localisation of high- and low-momentum zones is introduced. Finally, an accurate law to predict the transition location is provided, taking into account both T u and L, valid for both the transition scenarios.

Files in this item

Name:
Dynfluid-EP-Cherubini-2014.pdf
Size:
2.656Mb
Format:
PDF
View/Open

Collections

  • Dynamique des Fluides (DynFluid)

Related items

Showing items related by title, author, creator and subject.

  • Computing heteroclinic orbits using adjoint-based methods 
    Article dans une revue avec comité de lecture
    FARANO, Mirko; CHERUBINI, Stefania; ROBINET, Jean-Christophe; DE PALMA, Pietro; SCHNEIDER, T. M. (Cambridge University Press (CUP), 2018)
    Transitional turbulence in shear flows is supported by a network of unstable exact invariant solutions of the Navier–Stokes equations. The network is interconnected by heteroclinic connections along which the turbulent ...
  • Linear and nonlinear optimal growth mechanisms for generating turbulent bands 
    Article dans une revue avec comité de lecture
    PARENTE, ENZA; ROBINET, Jean-Christophe; DE PALMA, Pietro; CHERUBINI, Stefania (Cambridge University Press, 2022)
    Recently, many authors have investigated the origin and growth of turbulent bands in shear flows, highlighting the role of streaks and their inflectional instability in the process of band generation and sustainment. ...
  • Continuing invariant solutions towards the turbulent flow 
    Article dans une revue avec comité de lecture
    PARENTE, Enza; FARANO, Mirko; ROBINET, Jean-Christophe; DE PALMA, Pietro; CHERUBINI, Stefania (The Royal Society Publishing, 2022-05)
    A new mathematical framework is proposed for characterizing the coherent motion of fluctuations around a mean turbulent channel flow. We search for statistically invariant coherent solutions of the unsteady Reynolds-averaged ...
  • Modal and nonmodal stability of a stably stratified boundary layer flow 
    Article dans une revue avec comité de lecture
    PARENTE, Enza; ROBINET, Jean-Christophe; DE PALMA, Pietro; CHERUBINI, Stefania (American Physical Society, 2020)
    The modal and nonmodal linear stability of a stably stratified Blasius boundary layer flow, composed of a velocity and a thermal boundary layer, is investigated. The temporal and spatial linear stability of such flow is ...
  • Global stability analysis of lifted diffusion flames 
    Article dans une revue avec comité de lecture
    MANCINI, C.; FARANO, Mirko; DE PALMA, Pietro; ROBINET, Jean-Christophe; CHERUBINI, Stefania (Elsevier, 2017)
    This work describes the development of a method for the global hydrodynamic stability analysis of diffusion flames. The low-Machnumber (LMN) Navier–Stokes (NS) equations for reacting flows are solved together with a transport ...

Browse

All SAMCommunities & CollectionsAuthorsIssue DateCenter / InstitutionThis CollectionAuthorsIssue DateCenter / Institution

Newsletter

Latest newsletterPrevious newsletters

Statistics

Most Popular ItemsStatistics by CountryMost Popular Authors

ÉCOLE NATIONALE SUPERIEURE D'ARTS ET METIERS

  • Contact
  • Mentions légales

ÉCOLE NATIONALE SUPERIEURE D'ARTS ET METIERS

  • Contact
  • Mentions légales