Now showing items 1-20 of 73

  • A filtered kinetic energy preserving finite volumes scheme for compressible flows 

    Baez Vidal, Aleix; Lehmkuhl Barba, Oriol; Pérez Segarra, Carlos David; Oliva Llena, Asensio (2012)
    Conference report
    Open Access
    The Kinetic Energy Preserving Scheme (KEP) for compressible flows has been shown to solve 1-D shock waves without smearing them. The method does not add numerical diffusion to solutions but, as a counterpart, it needs ...
  • A finite-volume/level-set method for simulating two-phase flows on unstructured grids 

    Balcázar Arciniega, Néstor; Jofre Cruanyes, Lluís; Lehmkuhl Barba, Oriol; Castro González, Jesús; Rigola Serrano, Joaquim (2014-09)
    Article
    Restricted access - publisher's policy
    The conservative level-set method for capturing the interface between two fluids is combined with a variable density projection scheme to simulate incompressible two-phase flows on unstructured meshes. All equations are ...
  • A parallel three-dimensional radial basis function interpolation method for unstructured dynamic meshes 

    Estruch Pérez, Olga; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Pérez Segarra, Carlos David (2011)
    Conference lecture
    Open Access
    A radial basis function (RBF) interpolation method is implemented to be applied in computational fluid dynamics (CFD) problems with dynamic meshes. It is compared with the classic springs analogy smoothing, focusing on the ...
  • A PLIC-VOF implementation on parallel 3D unstructured meshes 

    Jofre Cruanyes, Lluís; Lehmkuhl Barba, Oriol; Castro González, Jesús; Oliva Llena, Asensio (2010)
    Conference lecture
    Restricted access - publisher's policy
    The numerical simulation of interfacial and free surface ows is a vast and interesting topic in the areas of engineering and fundamental physics, such as the study of liquid-gas interfaces, formation of droplets, bubbles ...
  • 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 ...
  • Assessment of the symmetry-preserving regularization model on complex flows using unstructured grids 

    Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Rodríguez Pérez, Ivette María; Pérez Segarra, Carlos David; Oliva Llena, Asensio (2012-05-15)
    Article
    Restricted access - publisher's policy
    The main objective of the present paper is the assessment of symmetry-preserving regularization models on unstructured meshes. Three different test cases have been studied: the impinging jet flow, the flow past a circular ...
  • CFD simulation of the thermal behavior of a wind mill power generator nacelle 

    Colomer Rey, Guillem; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Oliva Llena, Asensio (2009)
    Conference lecture
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    In this work we use the Large Eddy Simulation model to predict the thermal behavior of the air inside of a wind generator nacelle, where several elements with di erent thermal characteristics are found. Outside air enters ...
  • Combined heat and moisture transfer in buildings systems 

    Damle, Rashmin; Lehmkuhl Barba, Oriol; Rigola Serrano, Joaquim; Oliva Llena, Asensio (2012)
    Conference report
    Restricted access - publisher's policy
    Temperature and humidity are the two main parameters indicating the comfort level of the building occupants. Although the effect of temperature is taken into account in thermal simulation of buildings, the moisture transfer ...
  • Detailed numerical model for the resolution of molten salt storage tanks for CSP plants 

    Pérez Segarra, Carlos David; Rodríguez Pérez, Ivette María; Oliva Llena, Asensio; Torras Ortíz, Santiago; Lehmkuhl Barba, Oriol (2012)
    Conference report
    Open Access
    Considering the state-of-the-art in TES technologies, two-tank indirect system using molten salt is the most widespread within CSP plants. However, current techniques for design and optimization, as well as, for assessing ...
  • Detailed numerical study of turbulent flows in air curtains 

    Jaramillo Ibarra, Julian Ernesto; Pérez Segarra, Carlos David; Lehmkuhl Barba, Oriol; Oliva Llena, Asensio (2010)
    Conference lecture
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    Air curtains are generally a set of vertical or horizontal plane jets used as ambient separator. In order to prevent entrainment, a good air curtain should provide a jet with low turbulence level, enough momentum to ...
  • Direct numerical simulation and Large-Eddy simulations of the turbulent flow around a NACA-0012 airfoil 

    Lehmkuhl Barba, Oriol; Baez Vidal, Aleix; Rodríguez Pérez, Ivette María; Pérez Segarra, Carlos David (2011)
    Conference report
    Open Access
    This paper investigates the capabilities of two subgrid-scale (SGS) models for predicting the complex flow in transitional separated bubbles. We consider here the flow over a NACA 0012 airfoil at Reynolds number Re = 5×10 ...
  • Direct numerical simulation of a NACA0012 in full stall 

    Rodríguez Pérez, Ivette María; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Oliva Llena, Asensio (2013-10-15)
    Article
    Open Access
    This work aims at investigating the mechanisms of separation and the transition to turbulence in the separated shear-layer of aerodynamic profiles, while at the same time to gain insight into coherent structures formed ...
  • Direct Numerical Simulation of the flow over a sphere at Re = 3700 

    Rodríguez Pérez, Ivette María; Borrell Pol, Ricard; Lehmkuhl Barba, Oriol; Oliva Llena, Asensio; Pérez Segarra, Carlos David (2009)
    Conference lecture
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    The direct numerical simulation of the flow past a sphere at Re=3700 is presented. The computations are carried out with a parallel unstructured symmetry preserving information for accurate solving complex geometries. As ...
  • Direct numerical simulation of the flow over a sphere at Re = 3700 

    Rodríguez Pérez, Ivette María; Borrell Pol, Ricard; Lehmkuhl Barba, Oriol; Pérez Segarra, Carlos David; Oliva Llena, Asensio (2011-05-19)
    Article
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    The direct numerical simulation of the flow over a sphere is performed. The computations are carried out in the sub-critical regime at Re = 3700 (based on the free-stream velocity and the sphere diameter). A parallel ...
  • Direct numerical simulation of the flow over a spherical bubble in a turbulent pipe flow 

    Jofre Cruanyes, Lluís; Balcázar Arciniega, Néstor; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Castro González, Jesús (International Association for Computational Mechanics (IACM), 2014)
    Conference report
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    This work aims at investigating, by means of a direct numerical simulation, the flow over a clean spherical bubble fixed on the axis of a turbulent pipe flow. The simulation is performed by means of a parallel unstructured ...
  • Direct Numerical Simulation of the turbulent flow around a NACA 0012 airfoil at different angles of attack 

    Baez Vidal, Aleix; Lehmkuhl Barba, Oriol; Rodríguez Pérez, Ivette María; Pérez Segarra, Carlos David (2011)
    Conference report
    Open Access
    Direct numerical simulations (DNS) of the flow dynamics over a NACA 0012 airfoil at Reynolds number Re = 5×104 at different angles of attack are presented. The dynamic of the large separation bubble, characterised by laminar ...
  • Direct numerical simulation of turbulent wakes: flow past a sphere at Re=5000 

    Rodríguez Pérez, Ivette María; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Oliva Llena, Asensio; Pérez Segarra, Carlos David (2010)
    Conference report
    Open Access
    The flow around bluff bodies is of great interest for a large number of engineering applications such as vehicle aerodynamics, cooling devices using forced convection, heat transfer enhancement using droplets, among ...
  • Direct numerical simulation of viscoplastic-type non-Newtonian fluid flows in stenosed arteries 

    Carmona Muñoz, Ángel; Lehmkuhl Barba, Oriol; Pérez Segarra, Carlos David; Oliva Llena, Asensio (2013)
    Conference report
    Restricted access - publisher's policy
    The aim of this work is to provide DNS solutions for turbulence flows of viscoplastic-type non-Newtonian fluids and thus contribute to gain insight into the underlying physics of the non-Newtonian turbulent flows. This ...
  • Direct numerical simulations and symmetry preserving regularization simulations of the flow over a circular cylinder at Reynolds number 3900 

    Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Pérez Segarra, Carlos David; Chiva Segura, Jorge; Oliva Llena, Asensio (2009-09-14)
    Conference lecture
    Restricted access - publisher's policy
    Flow around cylindrical structures is of relevance for many practical applications. Knowledge of flow-related unsteady loading of such structures is crucial for hydro - and aerodynamic control and design. Recenty, the ...
  • Energy simulation of buildings with a modular object-oriented tool 

    Mohan Damle, Rashmin; Lehmkuhl Barba, Oriol; Colomer Rey, Guillem; Rodríguez Pérez, Ivette María (2011)
    Conference report
    Open Access
    The aim of this work is to develop a modular object-oriented tool “NEST” (Numerical Edifice Simulation Tool) for the energy simulation of buildings, which can be coupled with a parallel CFD software. For this purpose, a ...