Assessment and Comparison of a Recent Kinematic Sensitive Subgrid Length Scale in Hybrid RANS-LES

  • A. Pont-VílchezEmail author
  • F. X. Trias
  • A. Revell
  • A. Oliva
Conference paper
Part of the Notes on Numerical Fluid Mechanics and Multidisciplinary Design book series (NNFM, volume 143)


A recent kinematic sensitive subgrid length scale, \(\varDelta _{lsq}\), initially developed for LES applications, is now considered for DES. Even though it is presented as a subgrid length scale, instead of a grey area mitigation (GAM) technique, this initial study shows how it could also be a good and natural approach for addressing this well-known DES shortcoming. In this paper, the \(\varDelta _{lsq}\) has been compared with a well-known kinematic sensitive length scale, \({\tilde{\varDelta }_{\omega }}\). It includes a mesh resilience and a shear layer delay study with a Decaying Homogeneous Isotropic Turbulence configuration and two Backward Facing Step configurations, respectively. Encouraging results have been obtained, indicating \(\varDelta _{lsq}\) as a subgrid length scale to be considered.


Hybrid RANS-LES Gray Area Mitigation Subgrid Length Scale 



This work has been financially supported by the Ministerio de Economía y Competitividad, Spain (No. ENE2017-88697-R). A.P.V. is supported by a FI-DGR 2016 predoctoral contract (No. 2018FI_B2_00072) financed by Generalitat de Catalunya, Spain. F.X.T. is supported by a Ramón y Cajal postdoctoral Contract (No. RYC-2012-11996) financed by the Ministerio de Economía y Competitividad, Spain.


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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • A. Pont-Vílchez
    • 1
    Email author
  • F. X. Trias
    • 1
  • A. Revell
    • 2
  • A. Oliva
    • 1
  1. 1.Heat and Mass Transfer Technological Center (CTTC)Universitat Politècnica de Catalunya-BarcelonaTech (UPC)BarcelonaSpain
  2. 2.School of MACEUniversity of ManchesterManchesterUK

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