Now showing items 1-20 of 78

  • Algebraic implementation of a flux limiter for heterogeneous computing 

    Valle Marchante, Nicolás; Álvarez Farré, Xavier; Trias Miquel, Francesc Xavier; Castro González, Jesús; Oliva Llena, Asensio (2018)
    Conference report
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  • An efficient Two-Layer wall model for accurate numerical simulations of aeronautical applications 

    Calafell Sandiumenge, Joan; Trias Miquel, Francesc Xavier; Oliva Llena, Asensio (2019)
    Conference report
    Open Access
    Two-Layer wall models have been widely studied since they allow wall modeled Large Eddy Simulationsof general non-equilibrium flows. However, they are plagued by two persistent problems, the "log-layermismatch" and the ...
  • An efficient two-layer wall model for high Reynolds number large eddy simulation 

    Calafell Sandiumenge, Joan; Trias Miquel, Francesc Xavier; Oliva Llena, Asensio (International Centre for Numerical Methods in Engineering (CIMNE), 2018)
    Conference report
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    Wall-bounded flows at high Reynolds number are an important research field given that they are present in many important industrial applications. Nonetheless, the use of accurate numerical methodologies such as Large Eddy ...
  • An energy-preserving level set method for multiphase flows 

    Valle Marchante, Nicolás; Trias Miquel, Francesc Xavier; Castro González, Jesús (2020-01-01)
    Article
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    The computation of multiphase flows presents a subtle energetic equilibrium between potential (i.e., surface) and kinetic energies. The use of traditional interface-capturing schemes provides no control over such a dynamic ...
  • An eulerian-lagrangian modeling of fluidized bed 

    Zhang, Hao; Yuan-Qiang, Tan; Dong-Min, Yang; Trias Miquel, Francesc Xavier; Sheng, Yong; Oliva Llena, Asensio (2013)
    Conference report
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    The particle motions in a fluidized bed were numerically simulated using a Eulerian-Lagrangian model. The solid phase was modelled via the Discrete Element Method (DEM) while the hydrodynamic model of the fluid phase was ...
  • A new subgrid characteristic length for turbulence simulations on anisotropic grids 

    Trias Miquel, Francesc Xavier; Gorobets, Andrei; Silvis, Maurits; Verstappen, Roel; Oliva Llena, Asensio (2017-11-29)
    Article
    Open Access
    Direct numerical simulations of the incompressible Navier-Stokes equations are not feasible yet for most practical turbulent flows. Therefore, dynamically less complex mathematical formulations are necessary for coarse-grained ...
  • An OpenCL-based parallel CFD code for simulations on hybrid systems with massively-parallel accelerators 

    Gorobets, Andrei; Trias Miquel, Francesc Xavier; Oliva Llena, Asensio (Elsevier, 2013)
    Conference report
    Open Access
    A parallel finite-volume CFD algorithm for modeling of incompressible flows on hybrid supercomputers is presented. It is based on a symmetry-preserving high-order numerical scheme for structured meshes. A multilevel ...
  • 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, ...
  • A Projected Ghost Fluid Method for a mimetic approach for extreme contrast interfaces in multiphase flows 

    Valle Marchante, Nicolás; Trias Miquel, Francesc Xavier; Castro González, Jesús; Oliva Llena, Asensio (2018)
    Conference report
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    In the context of a multimaterial domain, the GFM for the Laplacian operator is reformulated from an algebraic perspective, where operators are represented by matrices. From this perspective, a whole new level of analysis ...
  • A self-adaptive strategy for the time integration of navier-stokes equations 

    Trias Miquel, Francesc Xavier; Lehmkuhl Barba, Oriol (2011-08)
    Article
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    An efficient self-adaptive strategy for the explicit time integration of Navier-Stokes equations is presented. Unlike the conventional explicit integration schemes, it is not based on a standard CFL condition. Instead, the ...
  • 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
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    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 ...
  • A simple optimization approach for the insulation thickness distribution in household refrigerators 

    Trias Miquel, Francesc Xavier; Oliet Casasayas, Carles; Rigola Serrano, Joaquim; Pérez Segarra, Carlos David (Elsevier, 2018-09)
    Article
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    Determination of the optimal insulation thickness is of great relevance in many thermal engineering applications. In this paper, a simple optimization strategy based on the Lagrange multipliers is presented. The optimal ...
  • Assessment and comparison of a recent kinematic sensitive subgrid length scale in Hybrid RANS-LES 

    Pont Vilchez, Arnau; Trias Miquel, Francesc Xavier; Revell, Alistair; Oliva Llena, Asensio (Springer Nature, 2020)
    Conference report
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    A recent kinematic sensitive subgrid length scale, Δlsq, 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) ...
  • A time-average filtering technique to improve the efficiency of two-layer wall models for large eddy simulation in complex geometries 

    Calafell Sandiumenge, Joan; Trias Miquel, Francesc Xavier; Lehmkuhl Barba, Oriol; Oliva Llena, Asensio (Elsevier, 2019-06-30)
    Article
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    Two-Layer wall models have been recurrently studied since they represent a good physical model for Large Eddy Simulations with underresolved wall regions. Specifically, those based on the Reynolds Averaged Navier-Stokes ...
  • 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)
    Conference lecture
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    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 a new subgrid characteristic length for LES 

    Trias Miquel, Francesc Xavier; Gorobets, Andrey; Duben, Alexey; Oliva Llena, Asensio (Keldysh Institute of Applied Mathematics, 2016)
    Conference report
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  • 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
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    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 ...
  • Building proper invariants for eddy-viscosity subgrid-scale models 

    Trias Miquel, Francesc Xavier; Folch, David; Gorobets, Andrei; Oliva Llena, Asensio (2015-06-23)
    Article
    Open Access
    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. ...
  • Building proper invariants for large eddy simulation 

    Trias Miquel, Francesc Xavier; Folch, David; Gorobets, Andrei; Oliva Llena, Asensio (Springer, 2015)
    Conference report
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  • Building proper invariants for subgrid-scale eddy-viscosity models 

    Trias Miquel, Francesc Xavier; Folch, David; Gorobets, Andrei; Oliva Llena, Asensio (2015)
    Conference report
    Restricted access - publisher's policy
    Since direct simulations of the incompressible Navier-Stokes equations are limited to relatively low-Reynolds numbers, dynamically less complex mathematical formulations are necessary for coarse-grain simulations. ...