Ara es mostren els items 1-20 de 25

  • A simple approach to discretize the viscous term with spatially varying (eddy-)viscosity 

    Trias Miquel, Francesc Xavier; Gorobets, Andrei; Oliva Llena, Asensio (2013-11-15)
    Article
    Accés restringit per política de l'editorial
    A simple approach to discretize the viscous dissipation term in the incompressible Navier–Stokes equations with spatially varying viscosity is presented. Unlike the case where the viscosity remains constant, its discretization ...
  • Blending regularization and large-eddy simulation. From homogeneous isotropic turbulence to wind farm boundary layers 

    Folch Flórez, David; Trias Miquel, Francesc Xavier; Gorobets, Andrei; Oliva Llena, Asensio (2013)
    Comunicació de congrés
    Accés restringit per política de l'editorial
    The incompressible Navier-Stokes equations form an excellent mathematical model for turbulent flows. However, direct simulations at high Reynolds numbers are not feasible because the convective term produces far too many ...
  • Building proper invariants for eddy-viscosity subgrid-scale models 

    Trias Miquel, Francesc Xavier; Folch, David; Gorobets, Andrei; Oliva Llena, Asensio (2015-06-23)
    Article
    Accés obert
    Direct simulations of the incompressible Navier-Stokes equations are limited to relatively low-Reynolds numbers. Hence, dynamically less complex mathematical formulations are necessary for coarse-grain simulations. ...
  • Direct numerical simulation of a differentially heated cavity of aspect ratio 4 with Rayleigh numbers up to 10(11) - Part I: Numerical methods and time-averaged flow 

    Trias Miquel, Francesc Xavier; Gorobets, Andrei; Soria Guerrero, Manel; Oliva Llena, Asensio (2010-01-31)
    Article
    Accés restringit per política de l'editorial
    A set of direct numerical simulations of a differentially heated cavity of aspect ratio 4 with adiabatic horizontal walls is presented. The five configurations selected here (Rayleigh numbers based on the cavity height ...
  • Direct numerical simulation of a differentially heated cavity of aspect ratio 4 with Rayleigh numbers up to 10(11) - Part II: Heat transfer and flow dynamics 

    Trias Miquel, Francesc Xavier; Gorobets, Andrei; Soria Guerrero, Manel; Oliva Llena, Asensio (2010-01-31)
    Article
    Accés restringit per política de l'editorial
    This is the second of a two-part paper on five direct numerical simulations of a differentially heated cavity of aspect ratio 4 with adiabatic horizontal walls (Rayleigh numbers based on the cavity height. The numerical ...
  • DNS of turbulent natural convection flows on the MareNostrum supercomputer 

    Trias Miquel, Francesc Xavier; Gorobets, Andrei; Soria Guerrero, Manel; Oliva Llena, Asensio (2009)
    Article
    Accés restringit per política de l'editorial
    A code for the direct numerical simulation (DNS) of incompressible turbulent flows that provides a fairly good scalability for a wide range of computer architectures has been developed. The spatial discretization of the ...
  • Efficiency of large-scale CFD simulations on modern supercomputers using thousands of CPUS and hybrid MPI+OPENMP parallelization 

    Gorobets, Andrei; Borrell Pol, Ricard; Trias Miquel, Francesc Xavier; Kozubskaya, T.K.; Oliva Llena, Asensio (2010)
    Comunicació de congrés
    Accés restringit per política de l'editorial
    This work represents an experience in using the hybrid parallel model to perform large-scale DNS. Advantages of the hybrid approach compared to the MPI-only approach are presented and discussed. The use of OpenMP in addition ...
  • From extruded-2D to fully-3D geometries for DNS: a multigrid-based extension of the Poisson solver 

    Gorobets, Andrei; Trias Miquel, Francesc Xavier; Soria Guerrero, Manel; Pérez Segarra, Carlos David; Oliva Llena, Asensio (2010)
    Article
    Accés restringit per política de l'editorial
    Direct numerical simulation (DNS) of incompressible flows is an essential tool for improving the understanding of the physics of turbulence and for the development of better turbulence models. The Poisson equation, the ...
  • Hybrid MPI+OpenMP parallelization of a Navier-Stokes solver for large-scale DNS 

    Gorobets, Andrei; Trias Miquel, Francesc Xavier; Borrell Pol, Ricard; Soria Guerrero, Manel; Oliva Llena, Asensio (2011)
    Comunicació de congrés
    Accés restringit per política de l'editorial
    This work presents a parallel Navier-Stokes solver for the large-scale direct numerical simulation (DNS) of incompressible flows with one periodic direction. It is based on a scalable Poisson solver that combines an FFT ...
  • Hybrid MPI+OpenMP parallelization of an FFT-based 3D Poisson solver that can reach 100000 CPU cores 

    Gorobets, Andrei; Trias Miquel, Francesc Xavier; Borrell Pol, Ricard; Soria Guerrero, Manel; Oliva Llena, Asensio (2011)
    Text en actes de congrés
    Accés obert
    This work is devoted to the development of efficient parallel algorithms for the direct numerical simulation (DNS) of incompressible flows on modern supercomputers. A Poisson solver for problems with one uniform periodic ...
  • Hybrid MPI+OpenMP parallelization of an FFT-based 3D Poisson solver with one periodic direction 

    Gorobets, Andrei; Trias Miquel, Francesc Xavier; Borrell Pol, Ricard; Lehmkuhl Barba, Oriol; Oliva Llena, Asensio (2011-10)
    Article
    Accés restringit per política de l'editorial
    This work is devoted to the development of efficient parallel algorithms for the direct numerical simulation (DNS) of incompressible flows on modern supercomputers. In doing so, a Poisson equation needs to be solved at ...
  • 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)
    Text en actes de congrés
    Accés obert
    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 ...
  • Parameter-free modelling of a turbulent differentially heated cavity with Rayleigh number up to 10e11 

    Trias Miquel, Francesc Xavier; Soria Guerrero, Manel; Gorobets, Andrei; Verstappen, R.W.C.P. (2009-09-14)
    Comunicació de congrés
    Accés restringit per política de l'editorial
    Since direct numerical simulations of natural convection in a differentially heated cavity cannot be performed at high Rayleigh numbers, a dynamically less complex mathematical formulation is sought. In the quest for such ...
  • Parameter-free symmetry-preserving regularization modeling of a turbulent differentially heated cavity 

    Trias Miquel, Francesc Xavier; Verstappen, R.W.C.P.; Gorobets, Andrei; Soria Guerrero, Manel; Oliva Llena, Asensio (2010-06-23)
    Article
    Accés restringit per política de l'editorial
    Since direct numerical simulations of buoyancy driven flows cannot be computed at high Rayleigh numbers, a dynamically less complex mathematical formulation is sought. In the quest for such a formulation, we consider ...
  • Regularization modeling of wall-bounded turbulent flows 

    Trias Miquel, Francesc Xavier; Gorobets, Andrei; Verstappen, R.W.C.P.; Oliva Llena, Asensio (2010)
    Comunicació de congrés
    Accés restringit per política de l'editorial
    Since direct numerical simulations cannot be computed at high Reynolds numbers, a dynamically less complex formulation is sought. In the quest for such a formulation, we consider regularizations of the convective term ...
  • Spectrally-consistent regularization modeling at very high Rayleigh numbers 

    Trias Miquel, Francesc Xavier; Gorobets, Andrei; Verstappen, R.W.C.P.; Oliva Llena, Asensio (Begell House, 2012)
    Text en actes de congrés
    Accés restringit per política de l'editorial
    The incompressible Navier-Stokes equations constitute an excellent mathematical modelization of turbulence. Unfortunately, attempts at performing direct simulations are limited to relatively low-Rayleigh numbers because ...
  • Spectrally-consistent regularization modeling of turbulent natural convection flows 

    Trias Miquel, Francesc Xavier; Verstappen, R.W.C.P.; Gorobets, Andrei; Oliva Llena, Asensio (Université de Poitiers, 2012)
    Text en actes de congrés
    Accés obert
    The incompressible Navier-Stokes equations constitute an excellent mathematical modelization of turbulence. Unfortunately, attempts at performing direct simulations are limited to relatively low-Reynolds numbers because ...
  • Spectrally-consistent regularization modeling of wind farm boundary layers 

    Trias Miquel, Francesc Xavier; Folch, David; Gorobets, Andrei; Oliva Llena, Asensio (2012)
    Text en actes de congrés
    Accés obert
    The incompressible Navier-Stokes equations constitute an excellent mathematical modelization of turbulence. Unfortunately, attempts at performing direct simulations are limited to relatively low-Reynolds numbers because ...
  • 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)
    Text en actes de congrés
    Accés restringit per política de l'editorial
    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 ...
  • Symmetry-preserving regularization of wall-bounded turbulent flows 

    Trias Miquel, Francesc Xavier; Gorobets, Andrei; Verstappen, R.W.C.P.; Oliva Llena, Asensio (2011)
    Comunicació de congrés
    Accés restringit per política de l'editorial
    The incompressible Navier-Stokes equations constitute an excellent mathematical modelization of turbulence. Unfortunately, attempts at performing direct simulations are limited to relatively low-Reynolds numbers because ...