Now showing items 1-20 of 21

  • A level-set aided single-phase model for the numerical simulation of free-surface flow on unstructured meshes 

    Schillaci, Eugenio; Jofre Cruanyes, Lluís; Balcázar Arciniega, Néstor; Lehmkuhl, Oriol; Oliva Llena, Asensio (Elsevier, 2016-11-25)
    Article
    Open Access
    A new single-phase scheme for the numerical simulation of free-surface problems on 3-D unstructured meshes is presented. The flow field is obtained from the discrete solution of the incompressible Navier-Stokes equations, ...
  • A low-dissipation finite element scheme for scale resolving simulations of turbulent flows 

    Lehmkuhl, Oriol; Houzeaux, Guillaume; Owen, Herbert; Chrysokentis, Giorgios; Rodríguez Pérez, Ivette María (2019-08-01)
    Article
    Restricted access - publisher's policy
    The present work extends the conservative convective scheme proposed by Charnyi et al. (2017) [13], originally formulated for mixed finite elements and tested in laminar flows, to equal order finite elements. A non-incremental ...
  • Boundary layer flow control using synthetic jets on the flow over a NACA 0012 airfoil 

    Duran, David; Rodríguez Pérez, Ivette María; Soria Guerrero, Manel; Lehmkuhl, Oriol (2017)
    Conference report
    Restricted access - publisher's policy
    Numerical simulations of the flow control using a synthetic jet are presented. The flow considered is around a NACA 0012 airfoil at Re = 5000 and the actuator is located at 6% of the chord from the leading edge. This work ...
  • Direct numerical simulation of multiphase flows with unstable interfaces 

    Schillaci, Eugenio; Lehmkuhl, Oriol; Antepara Zambrano, Óscar; Oliva Llena, Asensio (Institute of Physics (IOP), 2016-09-01)
    Article
    Open Access
    This paper presents a numerical model that intends to simulate efficiently the surface instability that arise in multiphase flows, typically liquid-gas, both for laminar or turbulent regimes. The model is developed on the ...
  • Evaluating the roles of detailed endocardial structures on right ventricular haemodynamics by means of CFD simulations 

    Sacco, Federica; Paun, Bruno; Lehmkuhl, Oriol; Iles, Tinen L.; Iaizzo, Paul A.; Houzeaux, Guillaume; Vázquez, Mariano; Butakoff, Constantine; Aguado-Sierra, Jazmin (Wiley, 2018-09)
    Restricted access - publisher's policy
    Computational modelling plays an important role in right ventricular (RV) haemodynamic analysis. However, current approaches use smoothed ventricular anatomies. The aim of this study is to characterise RV haemodynamics ...
  • Large eddy simulation for automotive aerodynamics with Alya 

    Lehmkuhl, Oriol; Chrysokentis, Georgios; Gomez, Samuel; Owen, Herbert (2018-07-09)
    Conference lecture
    Open Access
    The prodigious potential offered by the ever-growing computing infrastructure is fostering the use of large eddy simulation for automotive aerodynamics. This approach, which resolves the larger dynamically important eddies ...
  • Large eddy simulation of a turbulent diffusion flame: some aspects of subgrid modelling consistency 

    Ventosa Molina, Jordi; Lehmkuhl, Oriol; Pérez Segarra, Carlos David; Oliva Llena, Asensio (2017-04-26)
    Article
    Open Access
    In the context of Large Eddy Simulation (LES) solely for the momentum transport equation there may be found several models for the turbulent subgrid fluxes. Furthermore, among those relying on the eddy diffusivity approach, ...
  • Large-eddy simulations of the vortex-induced vibration of a low mass ratio two-degree-of-freedom circular cylinder at subcritical Reynolds numbers 

    Pastrana, Daniel; Cajas García, Juan Carlos; Lehmkuhl, Oriol; Rodríguez Pérez, Ivette María; Houzeaux, Guillaume (Elsevier, 2018-09)
    Article
    Restricted access - publisher's policy
    The vortex induced vibration phenomenon of a low mass ratio () two-degree-of-freedom circular cylinder at subcritical Reynolds numbers ( 5300, 11,000) has been investigated by means of large-eddy simulations. A low-dissipative ...
  • Left Ventricular Trabeculations Decrease the Wall Shear Stress and Increase the Intra-Ventricular Pressure Drop in CFD Simulations 

    Sacco, Federica; Paun, Bruno; Lehmkuhl, Oriol; Iles, Tinen L.; Iaizzo, Paul A.; Houzeaux, Guillaume; Vázquez, Mariano; Butakoff, Constantine; Aguado-Sierra, Jazmin (Frontiers Media, 2018-04-30)
    Article
    Open Access
    The aim of the present study is to characterize the hemodynamics of left ventricular (LV) geometries to examine the impact of trabeculae and papillary muscles (PMs) on blood flow using high performance computing (HPC). ...
  • LES-based Study of the Roughness Effects on the Wake of a Circular Cylinder from Subcritical to Transcritical Reynolds Numbers 

    Rodriguez, Ivette; Lehmkuhl, Oriol; Piomelli, Ugo; Chiva, Jorge; Borrell, Ricard; Oliva, Assensi (Springer Verlag, 2017-12)
    Article
    Open Access
    This paper investigates the effects of surface roughness on the flow past a circular cylinder at subcritical to transcritical Reynolds numbers. Large eddy simulations of the flow for sand grain roughness of size k/D = 0.02 ...
  • Noise Radiated by an Open Cavity at Low Mach Number 

    Martín Navarrete, Rocío; Soria Guerrero, Manel; Lehmkuhl, Oriol; Gorobets, Andrei; Cante Terán, Juan Carlos; Vidal Pairot, Pere (2018)
    Conference report
    Restricted access - publisher's policy
    The present work focuses on the study of noise generation and radiation of unsteady laminar flow over an open three dimensional cavity at low Mach number, that is of interest to understand noise generation mechanisms in ...
  • Numerical analysis of conservative unstructured discretisations for low Mach flows 

    Ventosa Molina, Jordi; Chiva Segura, Jorge; Lehmkuhl, Oriol; Muela Castro, Jordi; Pérez Segarra, Carlos David; Oliva Llena, Asensio (2016-12-01)
    Article
    Open Access
    Unstructured meshes allow easily representing complex geometries and to refine in regions of interest without adding control volumes in unnecessary regions. However, numerical schemes used on unstructured grids have to ...
  • Numerical simulation of roughness effects on the flow past a circular cylinder 

    Rodríguez Pérez, Ivette María; Lehmkuhl, Oriol; Piomelli, Ugo; Chiva Segura, Jorge; Borrell, Ricard; Oliva Llena, Asensio (Institute of Physics (IOP), 2016)
    Conference report
    Open Access
    In the present work large eddy simulations of the flow past a rough cylinder are performed at a Reynolds number of Re = 4.2 × 105 and an equivalent sand-grain surface roughness height ks = 0.02D. In order to determine the ...
  • On the boundary layer development and heat transfer from a sphere at moderate Reynolds numbers 

    Rodríguez Pérez, Ivette María; Lehmkuhl, Oriol; Soria Guerrero, Manel; Gómez, Samuel; Domínguez Pumar, Manuel; Kowalski, Lukasz (2018)
    Conference report
    Restricted access - publisher's policy
    Direct and large-eddy numerical simulations have been performed for a heated sphere at Reynolds numbers 200, 300, 500, 750, 1000 and 104, in the context of the development of a spherical wind sensor for Mars atmosphere ...
  • On the effects of free-stream turbulence intensity in the fluid flow and heat transfer from a sphere at subcritical Reynolds numbers 

    Rodríguez Pérez, Ivette María; Lehmkuhl, Oriol; Soria Guerrero, Manel; Gomez, Samuel; Domínguez Pumar, Manuel; Kowalski, Lukasz (2018)
    Conference lecture
    Restricted access - publisher's policy
    In this work, the effect of the free-stream turbu-lence on the heat transfer and the near wake behind a sphere is studied at moderate Reynolds numbers of ¿¿ ¿ ¿¿¿¿ and ¿¿ ¿ ¿¿¿. Turbulence delays the sep-aration of the ...
  • On the role of a centrifugal instability in the vortex-induced vibration of a two-degrees of freedom circular cylinder at moderate Reynolds numbers 

    Pastrana, Daniel; Cajas García, Juan Carlos; Lehmkuhl, Oriol; Rodríguez Pérez, Ivette María; Vázquez, Mariano; Houzeaux, Guillaume (2018)
    Conference report
    Restricted access - publisher's policy
    In this work, the formation and role of a centrifugal instability in the VIV phenomenon at moderate Reynolds numbers are investigated for the ¿rst time. Large eddy simulations of a low mass ratio (m = 2.6) two-degree-of-freedom ...
  • Regional aerosol deposition in the human airways: the SimInhale benchmark case and a critical assessment of in silico methods 

    Koullapis, P.; Kassinos, S.C.; Muela Castro, Jordi; Pérez Segarra, Carlos David; Rigola Serrano, Joaquim; Lehmkuhl, Oriol; Cui, Y.; Sommerfeld, M.; Elcner, J.; Jicha, M.; Saveljic, I.; Filipovic, N.; Lizal, F.; Nicolaou, L. (2017-09-07)
    Article
    Open Access
    Regional deposition effects are important in the pulmonary delivery of drugs intended for the topical treatment of respiratory ailments. They also play a critical role in the systemic delivery of drugs with limited lung ...
  • Regional aerosol deposition in the human airways: The SimInhale benchmark case and a critical assessment of in silico methods 

    Koullapis, P.; Kassinos, S.C.; Muela Castro, Jordi; Perez-Segarra, C.; Rigola, J.; Lehmkuhl, Oriol; Cui, Y.; Sommerfeld, M.; Jicha, M.; Saveljic, I.; Filipovic, N.; Lizal, F.; Nicolaou, L. (Elsevier, 2018-02-15)
    Article
    Open Access
    Regional deposition effects are important in the pulmonary delivery of drugs intended for the topical treatment of respiratory ailments. They also play a critical role in the systemic delivery of drugs with limited lung ...
  • Subject-variability effects on micron particle deposition in human nasal cavities 

    Calmet, Hadrien; Kleinstreuer, C.; Houzeaux, Guillaume; Kolanjiyil, A.V.; Lehmkuhl, Oriol; Olivares, Edgar; Vázquez, Mariano (Elsevier, 2018-01)
    Article
    Open Access
    Validated computer simulations of the airflow and particle dynamics in human nasal cavities are important for local, segmental and total deposition predictions of both inhaled toxic and therapeutic particles. Considering ...
  • Thermo-mechanical parametric analysis of packed-bed thermocline energy storage tanks 

    González Acedo, Ignacio; Pérez Segarra, Carlos David; Lehmkuhl, Oriol; Torras, Santiago; Oliva Llena, Asensio (2016-10-01)
    Article
    Open Access
    A packed-bed thermocline tank represents a proved cheaper thermal energy storage for concentrated solar power plants compared with the commonly-built two-tank system. However, its implementation has been stopped mainly due ...