Now showing items 1-20 of 109

    • A CFD-based surrogate model for predicting flow parameters in a ventilated room using sensor readings 

      Morozova, Nina; Trias Miquel, Francesc Xavier; Capdevila Paramio, Roser; Schillaci, Eugenio; Oliva Llena, Asensio (2022-07-01)
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      In this work, we develop a computational fluid dynamics (CFD)-based surrogate model, which predicts flow parameters under different geometrical configurations and boundary conditions in a benchmark case of a mechanically ...
    • A General Method to Compute Numerical Dispersion Error 

      Ruano Pérez, Jesús; Baez Vidal, Aleix; Rigola Serrano, Joaquim; Trias Miquel, Francesc Xavier (2021)
      Conference report
      Open Access
      This article presents a new methodology to compute numerical dispersion error. The analysis here presented is not restricted to uniform structured meshes nor linear discrete operators as it does not rely on sinusoids to ...
    • A hierarchical parallel implementation for heterogeneous computing. Application to algebra-based CFD simulations on hybrid supercomputers 

      Álvarez Farré, Xavier; Gorobets, Andrei; Trias Miquel, Francesc Xavier (Elsevier, 2021-01)
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      The quest for new portable implementations of simulation algorithms is motivated by the increasing variety of computing architectures. Moreover, the hybridization of high-performance computing systems imposes additional ...
    • A highly portable heterogeneous implementation of a Poisson solver for flows with one periodic direction 

      Alsalti Baldellou, Àdel; Trias Miquel, Francesc Xavier; Álvarez Farré, Xavier; Oliva Llena, Asensio (2021)
      Conference report
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      The portability of codes has become a major advantage given the continuous development of new architectures for numerical applications, as well as the progressive incorporation of accelerators in modern supercomputers. ...
    • A new general method to compute dispersion errors on Cartesian stretched meshes for both linear and non-linear operators 

      Ruano Pérez, Jesús; Baez Vidal, Aleix; Rigola Serrano, Joaquim; Trias Miquel, Francesc Xavier (2022-02-01)
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      The present article presents a new analysis for the dispersion error and the methodology to evaluate it numerically. Here we present the spectral properties of several convective schemes, including non-linear ones, on ...
    • 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 ...
    • 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 pure virtual approach for managing platform portability on hybrid supercomputers 

      Álvarez Farré, Xavier; Gorobets, Andrei; Alsalti Baldellou, Àdel; Trias Miquel, Francesc Xavier (2019)
      Conference report
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      Commonly, the development of scientific computing software follows a stencilbased approach: the numerical methods and algorithms are introduced into computing systems through stencil data structures and sweeps (i.e. ...
    • A self-adaptive strategy for the time integration of navier-stokes equations 

      Trias Miquel, Francesc Xavier; Lehmkuhl Barba, Oriol (2011-08)
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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)
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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
      Open Access
      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 ...
    • A symmetry-preserving second-order time-accurate PISO-based method 

      Komen, E.M.J.; Hopman, Johannes Arend; Frederix, E.M.A.; Trias Miquel, Francesc Xavier; Verstappen, Roel (Elsevier, 2021-07-15)
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      A new conservative symmetry-preserving second-order time-accurate PISO-based pressure-velocity coupling for solving the incompressible Navier-Stokes equations on unstructured collocated grids is presented in this paper. ...
    • 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
      Open Access
      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 ...
    • Advanced techniques for grau area mitigation in DES simulations and their effectes on the subsonic round jet acoustic spectra 

      Duben, Alexey; Ruano Pérez, Jesús; Trias Miquel, Francesc Xavier; Rigola Serrano, Joaquim (2021)
      Conference report
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      The research dedicated to the investigation of different gray-area mitigation approaches towards accurate aerodynamics and aeroacoustics is presented. The recent modifications of hybrid RANS-LES DDES approach based on ...
    • 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
      Open Access
      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 ...