Now showing items 1-12 of 12

    • A priori study of subgrid-scale features in turbulent Rayleigh-Bénard convection 

      Dabbagh, Firas; Trias Miquel, Francesc Xavier; Gorobets, Andrei; Oliva Llena, Asensio (2017-10-06)
      Article
      Open Access
      At the crossroad between flow topology analysis and turbulence modeling, a priori studies are a reliable tool to understand the underlying physics of the subgrid-scale (SGS) motions in turbulent flows. In this paper, ...
    • Building a proper tensor-diffusivity model for large-eddy simulation of buoyancy-driven flows 

      Trias Miquel, Francesc Xavier; Dabbagh, Firas; Gorobets, Andrei; Oliva Llena, Asensio (International Centre for Numerical Methods in Engineering (CIMNE), 2018)
      Conference report
      Restricted access - publisher's policy
      In this work, we plan to shed light on the following research question: can we ¿nd a nonlinear tensorial subgrid-scale (SGS) heat ¿ux model with good physical and numerical properties, such that we can obtain satisfactory ...
    • Direct numerical simulation of laminar and turbulent Rayleigh-Bénard convection 

      Dabbagh, Firas (Universitat Politècnica de Catalunya / Universitat de Barcelona, 2013-06)
      Master thesis
      Open Access
      The main aim of this work is understanding the phenomenon of B enard cells in laminar and turbulent regimes as an application of studying the air flow in the air gap and honey comb cells that installed in the flat plate ...
    • Fine-scale dynamics in turbulent Rayleigh-Bénard convection 

      Dabbagh, Firas; Trias Miquel, Francesc Xavier; Gorobets, Andrei; Oliva Llena, Asensio (Begell House, 2015)
      Conference report
      Restricted access - publisher's policy
      Small-scale universal features captured normally in many turbulent flows have been reviewed in Rayleigh-Bénard convection. Namely, dynamical Lagrangian representations of the velocity gradient tensor invariants have displayed ...
    • Flow topology and small-scale dynamics in turbulent Rayleigh-Bénard convection 

      Dabbagh, Firas (Universitat Politècnica de Catalunya, 2017-09-06)
      Doctoral thesis
      Open Access
      Without fluid turbulence, life might have rather different look. The atmosphere and oceans could nearly maintain a much larger temperature differences resulting in ultimate heating or cooling to the earth surface. The water ...
    • Flow topology dynamics in a three-dimensional phase space for turbulent Rayleigh-Bénard convection 

      Dabbagh, Firas; Trias Miquel, Francesc Xavier; Gorobets, Andrey; Oliva Llena, Asensio (2020-02-28)
      Article
      Open Access
    • New subgrid-scale models for large-eddy simulation of Rayleigh-Bénard convection 

      Dabbagh, Firas; Trias Miquel, Francesc Xavier; Gorobets, Andrei; Oliva Llena, Asensio (Institute of Physics (IOP), 2016)
      Conference report
      Open Access
      At the crossroad between flow topology analysis and the theory of turbulence, a new eddy-viscosity model for Large-eddy simulation has been recently proposed by Trias et al.[PoF, 27, 065103 (2015)]. The S3PQR-model has the ...
    • On a physically-consistent nonlinear subgrid-scale heat flux model for LES of buoyancy driven flows 

      Trias Miquel, Francesc Xavier; Dabbagh, Firas; Gorobets, Andrei; Oliva Llena, Asensio (2018)
      Conference report
      Restricted access - publisher's policy
      Small-scale dynamics is the spirit of turbulence physics. It delivers complex mechanisms when turbulence is purely sustained by buoyancy. This takes place in Rayleigh-Bénard convection (RBC). Most of the existing RBC ...
    • On a Proper Tensor-Diffusivity Model for Large-Eddy Simulation of Buoyancy-Driven Turbulence 

      Trias Miquel, Francesc Xavier; Dabbagh, Firas; Gorobets, Andrei; Oliet Casasayas, Carles (Springer, 2020-03-26)
      Article
      Open Access
      In this work, we aim to shed light to the following research question: can we find a nonlinear tensorial subgrid-scale (SGS) heat flux model with good physical and numerical properties, such that we can obtain satisfactory ...
    • On a proper tensor-diffusivity model for large-eddy simulations of buoyancy driven flows 

      Trias Miquel, Francesc Xavier; Dabbagh, Firas; Gorobets, Andrei; Oliva Llena, Asensio (2019)
      Conference report
      Restricted access - publisher's policy
    • On the evolution of flow topology in turbulent Rayleigh-Bénard convection 

      Dabbagh, Firas; Trias Miquel, Francesc Xavier; Gorobets, Andrei; Oliva Llena, Asensio (2016-11-22)
      Article
      Open Access
      Small-scale dynamics is the spirit of turbulence physics. It implicates many attributes of flow topology evolution, coherent structures, hairpin vorticity dynamics, and mechanism of the kinetic energy cascade. In this work, ...
    • Spectrally-consistent regularization of turbulent Rayleigh-Bénard convection 

      Dabbagh, Firas; Trias Miquel, Francesc Xavier; Gorobets, Andrei; Oliva Llena, Asensio (International Association for Computational Mechanics (IACM), 2014)
      Conference report
      Restricted access - publisher's policy
      Direct numerical simulation (DNS) of turbulent Rayleigh-Bénard convection in an air filled (Pr = 0,7) rectangular cell of squared cross-section with periodic boundary conditions in the span-wise direction, has been carried ...