Graphic summary
  • Show / hide key
  • Information


Scientific and technological production
  •  

1 to 50 of 111 results
  • A two-step monolithic method for efficient simulation of incompressible flows

     Ryzhakov, Pavel; Cotela Dalmau, Jordi; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    International journal for numerical methods in fluids
    Date of publication: 2014-04
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    We propose a simple technique for improving computational the eciency of monolithic velocity-pressure solvers for incompressible ow problems. The idea consists in solving the discrete non-linear system of governing equations in two steps: introducing \articial" compressibility rst and afterwards correcting the solution by solving the original incompressible system. The speed-up is obtained due to a better conditioning of the modied discrete system solved at the prediction step. The formulation can be easily implemented into existing monolithic codes requiring minor modication only. The paper concludes with two examples validating the formulation and facilitating the estimation of the obtained speed-up. For the tests chosen an average speed-up is appx. double, suggesting that the method is a feasible approach for incompressible flows' simulation.

    We propose a simple technique for improving computational the e ciency of monolithic velocity-pressure solvers for incompressible ow problems. The idea consists in solving the discrete non-linear system of governing equations in two steps: introducing \arti cial

  • Lagrangian analysis of multiscale particulate flows with the particle finite element method

     Oñate Ibáñez de Navarra, Eugenio; Celigueta Jordana, Miguel Angel; Latorre Sánchez, Salvador; Casas, Guillermo; Rossi, Riccardo; Rojek, J.
    Journal of Computational Particle Mechanics
    Date of publication: 2014-05
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    We present a Lagrangian numerical technique for the analysis of flows incorporating physical particles of different sizes. The numerical approach is based on the particle finite element method (PFEM) which blends concepts from particle-based techniques and the FEM. The basis of the Lagrangian formulation for particulate flows and the procedure for modelling the motion of small and large particles that are submerged in the fluid are described in detail. The numerical technique for analysis of this type of multiscale particulate flows using a stabilized mixed velocity-pressure formulation and the PFEM is also presented. Examples of application of the PFEM to several particulate flows problems are given.

  • Outstanding Paper Award

     Idelsohn Barg, Sergio Rodolfo; Nigro, Norberto; Gimenez, Juan Marcelo; Rossi, Riccardo; Marti, Julio Marcelo
    Award or recognition

     Share

  • Access to the full text
    Migration of a generic multi-physics framework to HPC environments  Open access

     Dadvand, Pooyan; Rossi, Riccardo; Gil Gómez, Maria Luisa; Martorell Bofill, Xavier; Cotela Dalmau, Jordi; Juanpere Cañameras, Edgar; Idelsohn Barg, Sergio Rodolfo; Oñate Ibáñez de Navarra, Eugenio
    Computers and fluids
    Date of publication: 2013-07-10
    Journal article

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    Creating a highly parallelizable code is a challenge specially for Distributed Memory Machines (DMMs). Moreover, algorithms and data structures suitable for these platforms can be very different from the ones used in serial code. For this reason, many programmers in the field prefer to start their own code from scratch. However, for an already existing framework supported by a long-time expertise the idea of transformation becomes attractive in order to reuse the effort done during years of development. In this presentation we explain how a relatively complex framework but with modular structure can be prepared for high performance computing with minimum modification. Kratos Multi-Physics [1] is an open source generic multi-disciplinary platform for solution of coupled problems consist of fluid, structure, thermal and electromagnetic fields. The parallelization of this framework is performed with objective of enforcing the less possible changes to its different solver modules and encapsulate the changes as much as possible in its common kernel. This objective is achieved thanks to the Kratos design and also innovative way of dealing with data transfers for a multi-disciplinary code. This work is completed by the migration of the framework from the 86× architecture to the Marenostrum Supercomputing platform. The migration has been verified by a set of benchmarks which show high scalability, from which we present the Telescope problem in this paper.

    Creating a highly parallelizable code is a challenge specially for distributed memory machines (DMMs). Moreover, algorithms and data structures suitable for these platforms can be very different from the ones used in serial code. For this reason, many programmers in the field prefer to start their own code from scratch. However, for an already existing framework supported by a long-time expertise the idea of transformation becomes attractive in order to reuse the effort done during years of development. In this presentation we explain how a relatively complex framework but with modular structure can be prepared for high performance computing with minimum modification. Kratos Multi-Physics [1] is an open source generic multi-disciplinary platform for solution of coupled problems consist of fluid, structure, thermal and electromagnetic fields. The parallelization of this framework is performed with objective of enforcing the less possible changes to its different solver modules and encapsulate the changes as much as possible in its common kernel. This objective is achieved thanks to the Kratos design and also innovative way of dealing with data transfers for a multi-disciplinary code. This work is completed by the migration of the framework from the x86 architecture to the Marenostrum Supercomputing platform. The migration has been verified by a set of benchmarks which show high scalability, from which we present the Telescope problem in this paper.

  • Access to the full text
    A portable OpenCL-based unstructured edge-based Finite Element Navier-Stokes solver on graphics hardware  Open access

     Rossi, Riccardo; Mossaiby, Farshid; Idelsohn Barg, Sergio Rodolfo
    Computers and fluids
    Date of publication: 2013-07
    Journal article

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    The rise of GPUs in modern high-performance systems increases the interest in porting portion of codes to such hardware. The current paper aims to explore the performance of a portable state-of-the-art FE solver on GPU accelerators. Performance evaluation is done by comparing with an existing highly-optimized OpenMP version of the solver. Code portability is ensured by writing the program using the OpenCL 1.1 specifications, while performance portability is sought through an optimization step performed at the beginning of the calculations to find out the optimal parameter set for the solver. The results show that the new implementation can be several times faster than the OpenMP version.

    The rise of GPUs in modern high-performance systems increases the interest in porting portion of codes to such hardware. The current paper aims to explore the performance of a portable state-of-the-art FE solver on GPU accelerators. Performance evaluation is done by comparing with an existing highly-optimized OpenMP version of the solver. Code portability is ensured by writing the program using the OpenCL 1.1 specifications, while performance portability is sought through an optimization step performed at the beginning of the calculations to find out the optimal parameter set for the solver. The results show that the new implementation can be several times faster than the OpenMP version.

  • Analysis of the discharge capacity of radial gated-spillways using CFD and ANN: Oliana Dam case study

     Salazar González, Fernando; Morán Moya, Rafael; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    Journal of hydraulic research
    Date of publication: 2013-03
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    The paper focuses on the analysis of radial-gated spillways, which is carried out by the solution of a numerical model based on the finite element method (FEM). The Oliana Dam is considered as a case study and the discharge capacity is predicted both by the application of a level-set-based free-surface solver and by the use of traditional empirical formulations. The results of the analysis are then used for training an artificial neural network to allow real-time predictions of the discharge in any situation of energy head and gate opening within the operation range of the reservoir. The comparison of the results obtained with the different methods shows that numerical models such as the FEM can be useful as a predictive tool for the analysis of the hydraulic performance of radial-gated spillways.

  • Parallel adaptive mesh refinement for incompressible flow problems

     Rossi, Riccardo; JORDI, COTELA DALMAU; Lafontaine, Nelson Maireni; Dadvand, Pooyan; Idelsohn Barg, Sergio Rodolfo
    Computers and fluids
    Date of publication: 2013-07
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    The present article describes a simple element-driven strategy for the conforming refinement of simplicial finite element meshes in a distributed environment. The proposed algorithm is effective both for local adaptive refinement and for the division of all the elements within an existing mesh. We aim to provide sufficient detail to allow the practical implementation of the algorithm, which can be coded with minimal effort provided that a distributed linear algebra library is available. The proposed refinement strategy is composed of three basic components: a global splitting strategy, an elemental splitting procedure and an error estimation technique, which are combined so to guarantee obtaining a conformant refined mesh. A number of benchmark examples show the capabilities of the proposed method. Error is estimated for the incompressible fluid-flow benchmarks using a novel indicator based on the computation of the sub-scale velocity.

  • A compressible Lagrangian framework for the simulation of the underwater implosion of large air bubbles

     Kamran, Kazem; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio; Idelsohn Barg, Sergio Rodolfo
    Computer methods in applied mechanics and engineering
    Date of publication: 2013-03
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • A fast and accurate method to solve the incompressible Navier-Stokes equations

     Idelsohn Barg, Sergio Rodolfo; Nigro, Norberto; Gimenez, Juan; Rossi, Riccardo; Marti, Julio Marcelo
    Engineering computations
    Date of publication: 2013-02
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • A compressible lagrangian framework for modeling the fluid-structure interaction in the underwater implosion of an aluminum cylinder

     Kamran, Kazem; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio; Idelsohn Barg, Sergio Rodolfo
    Mathematical models and methods in applied sciences
    Date of publication: 2013-02
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Access to the full text
    Modelling and simulation of the sea-landing of aerial vehicles using the Particle Finite Element Method  Open access

     Ryzhakov, Pavel; Rossi, Riccardo; Viña, Adria; Oñate Ibáñez de Navarra, Eugenio
    Ocean engineering
    Date of publication: 2013-07
    Journal article

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    In this paper the Particle Finite Element Method (PFEM) is applied to the simulation of the sea-landing of an unmanned aerial vehicle (UAV). The problem of interest consists in modelling the impact of the vehicle against the water surface, analyzing the main kinematic and dynamic quantities (such as loads exerted upon the capsule at the moment of the impact). The PFEM, a methodology well-suited for free-surface flow simulation is used for modelling the water while a rigid body model is chosen for the vehicle. The vehicle under consideration is characterized by low weight. This leads to difficulties in modelling the fluid¿structure interaction using standard Dirichlet¿Neumann coupling. We apply a modified partitioned strategy introducing the interface Laplacian into the pressure Poisson's equation for obtaining a convergent FSI solution. The paper concludes with an industrial example of a vehicle sea-landing modelled using PFEM.

    In this paper the Particle Finite Element Method (PFEM) is applied to the simulation of the sea-landing of an unmanned aerial vehicle (UAV). The problem of interest consists in modelling the impact of the vehicle against the water surface, analyzing the main kinematic and dynamic quantities (such as loads exerted upon the capsule at the moment of the impact). The PFEM, a methodology well-suited for free-surface flow simulation is used for modelling the water while a rigid body model is chosen for the vehicle. The vehicle under consideration is characterized by low weight. This leads to difficulties in modelling the fluid–structure interaction using standard Dirichlet–Neumann coupling. We apply a modified partitioned strategy introducing the interface Laplacian into the pressure Poisson's equation for obtaining a convergent FSI solution. The paper concludes with an industrial example of a vehicle sea-landing modelled using PFEM.

  • Analysis of the melting, burning and flame spread of polymers with the particle finite element method

     Oñate Ibáñez de Navarra, Eugenio; Marti, Julio Marcelo; Ryzhakov, Pavel; Rossi, Riccardo; Idelsohn Barg, Sergio Rodolfo
    Computer Assisted Methods in Engineering and Science
    Date of publication: 2013
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    A computational procedure for analysis of the melting, burning and flame spread of polymers under fire conditions is presented. The method, termed particle finite element method (PFEM), combines concepts from particle-based techniques with those of the standard finite element method (FEM). The key feature of the PFEM is the use of an updated Lagrangian description to model the motion of nodes (particles) in the thermoplastic material. Nodes are viewed as material points which can freely move and even separate from the main analysis domain representing, for instance, the effect of melting and dripping of polymer particles. A mesh connects the nodes defining the discretized domain where the governing equations are solved using the FEM. An incremental iterative scheme for the solution of the nonlinear transient coupled thermal-flow problem, including radiation, loss of mass by gasification and combustion is used. Examples of the possibilities of the PFEM for the modelling and simulation of the melting, burning and flame spread of polymers under different fire conditions are described.

  • A contact algorithm for shell problems via Delaunay-based meshing of the contact domain

     Kamran, Kazem; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    Computational Mechanics
    Date of publication: 2013-07
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    The simulation of the contact within shells, with all of its different facets, represents still an open challenge in Computational Mechanics. Despite the effort spent in the development of techniques for the simulation of general contact problems, an all-seasons algorithm applicable to complex shell contact problems is yet to be developed. This work focuses on the solution of the contact between thin shells by using a technique derived from the particle finite element method together with a rotation-free shell triangle. The key concept is to define a discretization of the contact domain (CD) by constructing a finite element mesh of four-noded tetrahedra that describes the potential contact volume. The problem is completed by using an assumed-strain approach to define an elastic contact strain over the CD.

  • An efficient edge-based level set finite element method for free surface flow problems

     Rossi, Riccardo; Larese, Antonia; Dadvand, Pooyan; Oñate Ibáñez de Navarra, Eugenio
    International journal for numerical methods in fluids
    Date of publication: 2013-02
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    We present an efficient technique for the solution of free surface flow problems using level set and a parallel edge-based finite elementmethod. An unstructured semi-explicit solution scheme is proposed. A custom data structure, obtained by blending node-based and edge-based approaches is presented so to allow a good parallel performance. In addition to standard velocity extrapolation (for the convection of the level set function), an explicit extrapolation of the pressure field is performed in order to impose both the pressure boundary condition and the volume conservation. The latter is also improved with a modification of the divergence free constrain. The method is shown to allow an efficient solution of both simple benchmark cases and complex industrial examples.

    We present an efficient technique for the solution of free surface flow problems using level set and a parallel edge-based finite elementmethod. An unstructured semi-explicit solution scheme is proposed. A custom data structure, obtained by blending node-based and edge-based approaches is presented so to allow a good parallel performance. In addition to standard velocity extrapolation (for the convection of the level set function), an explicit extrapolation of the pressure field is performed in order to impose both the pressure boundary condition and the volume conservation. The latter is also improved with a modification of the divergence free constrain. The method is shown to allow an efficient solution of both simple benchmark cases and complex industrial examples.

  • Advances in the particle finite element method (PFEM) for coupled problems in engineering

     Oñate Ibáñez de Navarra, Eugenio; Idelsohn Barg, Sergio Rodolfo; Celigueta Jordana, Miguel Angel; Ryzhakov, Pavel; Martí, Julio; Carbonell Puigbo, Josep Maria; Suarez Arroyo, Benjamin; Salazar González, Fernando; Rossi, Riccardo
    Computational Methods for Coupled Problems in Science and Engineering
    Presentation's date: 2013-06-17
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Procedimiento de diseño de protecciones tipo repié para evitar la rotura por deslizamiento en masa de presas de escollera sometidas a percolaciones extremas

     Morán Moya, Rafael; Alves, Ricardo; Toledo Municio, Miguel Ángel; Larese, Antonia; Salazar González, Fernando; Rossi, Riccardo
    Jornadas de Ingeniería del Agua
    Presentation's date: 2013
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    La demanda de seguridad en infraestructuras críticas ha aumentado en los últimos años, especialmente en los países con mayor nivel de desarrollo económico y social. En estos países, el control del estado de la seguridad de estas infraestructuras y las medidas para disminuir los riesgos asociados en caso de avería están adquiriendo una gran relevancia, lo que se ha plasmado en unas normativas más exigentes. Las presas están dentro de este tipo de infraestructuras tanto por su interés estratégico como por los daños que pueden llegar a ocasionar en caso de un mal funcionamiento o de su eventual rotura. La tecnología de protecciones de presas surge como respuesta a esta demanda de seguridad y, por este motivo, ha experimentado un gran avance en las últimas décadas. Dentro de este artículo se va a describir la protección tipo repié y el procedimiento de diseño propuesto para evitar el deslizamiento en masa de presas con espaldón de aguas abajo de escollera, cuando se produce una filtración anormalmente elevada debido a un fallo en la impermeabilidad en el conjunto presa-cimiento. El artículo describe brevemente el estado del arte de la tecnología y de sus aplicaciones así como de la innovación conseguida en este campo a partir de las investigaciones desarrolladas en la Universidad Politécnica de Madrid (UPM), en colaboración con el Centro de Estudios Hidrográficos del CEDEX y el Centro Internacional de Métodos Numéricos en la Ingeniería (CIMNE), en el marco del proyecto de investigación del Plan Nacional denominado EDAMS, y cuyo resultado se ha plasmado en una tesis doctoral .

    La demanda de seguridad en infraestructuras críticas ha aumentado en los últimos años, especialmente en los países con mayor nivel de desarrollo económico y social. En estos países, el control del estado de la seguridad de estas infraestructuras y las medidas para disminuir los riesgos asociados en caso de avería están adquiriendo una gran relevancia, lo que se ha plasmado en unas normativas más exigentes. Las presas están dentro de este tipo de infraestructuras tanto por su interés estratégico como por los daños que pueden llegar a ocasionar en caso de un mal funcionamiento o de su eventual rotura. La tecnología de protecciones de presas surge como respuesta a esta demanda de seguridad y, por este motivo, ha experimentado un gran avance en las últimas décadas. Dentro de este artículo se va a describir la protección tipo repié y el procedimiento de diseño propuesto para evitar el deslizamiento en masa de presas con espaldón de aguas abajo de escollera, cuando se produce una filtración anormalmente elevada debido a un fallo en la impermeabilidad en el conjunto presa-cimiento. El artículo describe brevemente el estado del arte de la tecnología y de sus aplicaciones así como de la innovación conseguida en este campo a partir de las investigaciones desarrolladas en la Universidad Politécnica de Madrid (UPM), en colaboración con el Centro de Estudios Hidrográficos del CEDEX y el Centro Internacional de Métodos Numéricos en la Ingeniería (CIMNE), en el marco del proyecto de investigación del Plan Nacional denominado EDAMS, y cuyo resultado se ha plasmado en una tesis doctoral .

  • Modelación física y numérica de aliviaderos con cajeros altamente convergentes

     San Mauro, Javier; Salazar González, Fernando; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio; Morera, l.; Toledo Municio, Miguel Ángel; Morán Moya, Rafael; Caballero, F.J.; Martínez, B.; Guerrero, J.
    Jornadas de Ingeniería del Agua
    Presentation's date: 2013-10
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Access to the full text
    El papel de los modelos numéricos en la investigación y el diseño de aliviaderos de presas  Open access

     Salazar González, Fernando; San Mauro, Javier; Irazábal, Joaquín; Larese, Antonia; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio; Morán Moya, Rafael; Toledo Municio, Miguel Ángel
    Jornada Técnica Avances en Investigación Aplicada en Seguridad Hidráulica de Presas
    Presentation's date: 2013-06-20
    Presentation of work at congresses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    El Centro Internacional de Métodos Numéricos en Ingeniería (CIMNE) es un centro de investigación dependiente de la Generalidad de Cataluña y de la Universidad Politécnica de Cataluña creado en 1987. Su principal actividad es el desarrollo y aplicación de métodos numéricos innovadores para resolver problemas prácticos en diversos campos de la ingeniería, y se desarrolla fundamentalmente en el marco de proyectos de investigación nacionales e internacionales. En los últimos años el centro ha participado en diversos proyectos relacionados con la seguridad de presas, fundamentalmente hidráulica, pero también estructural, en cooperación con diversas empresas y organismos públicos de investigación como el CEDEX y la UPM. La presente comunicación describe brevemente los objetivos principales de los mencionados proyectos, haciendo hincapié en cómo la modelación numérica ha contribuido a alcanzarlos. Previamente se hace una breve introducción a las dos estrategias numéricas que se han empleado.

    El Centro Internacional de Métodos Numéricos en Ingeniería (CIMNE) es un centro de investigación dependiente del Gobierno de Cataluña y de la Universidad Politécnica de Cataluña creado en 1987. Su principal actividad es el desarrollo y aplicación de métodos numéricos innovadores para resolver problemas prácticos en diversos campos de la ingeniería, y se desarrolla fundamentalmente en el marco de proyectos de investigación nacionales e internacionales. En los últimos años el centro ha participado en diversos proyectos relacionados con la seguridad de presas, fundamentalmente hidráulica, pero también estructural, en cooperación con diversas empresas y organismos públicos de investigación como el CEDEX y la UPM. La presente comunicación describe brevemente los objetivos principales de los menciona dos proyectos, haciendo hincapié en cómo la modelación numérica ha contribuido a alcanzarlos.

  • Simulación de presas de escollera en condiciones de sobrevertido

     Larese, Antonia; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    Congress on Numerical Methods in Engineering
    Presentation's date: 2013-06
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • A combined Lagrangian-Eulerian technique for problems in geomechanics

     Larese, Antonia; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    Computational Methods for Coupled Problems in Science and Engineering
    Presentation's date: 2013-06
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • A compressible lagrangian framework for the simulation of underwater implosion problems  Open access

     Kamran, Kazem
    Defense's date: 2013-06-21
    Department of Strength of Materials and Structural Engineering, Universitat Politècnica de Catalunya
    Theses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    El desarrollo de métodos eficientes para modelar la dinámica de implosión presenta varios desafíos. El primero es una representación eficaz de la dinámica del sistema acoplado de aire-agua. El segundo es que el método tiene que permitir una detección exacta o un seguimiento adecuado de la interfase entre ambas fases. Por último el método tiene que ser capaz de resolver cualquier choque que podría generar en el aire o en el agua, sobre todo en la última fase del colapso. Nosotros presentamos un método numérico compresible y totalmente Lagrangiano para simular la implosión bajo el agua. Tanto el aire como el agua se consideran compresibles y las ecuaciones Lagrangianos para la hidrodinámica del choque se estabilizan mediante un método multiescala que es variacionalmente consistente. Se utiliza una definición de interfase que coincide perfectamente con los nodos. Ésta, nos facilita duplicar eficazmente las variables cinéticas como la presión y la densidad en los nodos de la interfase. Con el fin de obtener suficiente resolución alrededor de la interfase, la malla se genera de forma adaptativa y respetando la posición de la interfase. A continuación el método desarrollado se utiliza para simular la implosión bajo el agua de una burbuja cilíndrica del tamaño de un centímetro. Varios fenómenos se han capturado durante el colapso: un ciclo inmediato de colapso-crecimiento de la burbuja que ocurre en un espacio (0.3 mm) y tiempo (0.1 ms) bastante limitado, aparición de inestabilidades de tipo Rayleigh-Taylor en la interfase y formaron de varias ondas de choque que viajan tanto en el agua como en el aire. Después, seguimos el desarrollo del método para modelar la implosión bajo el agua de un contenedor metálico considerando una interacción monolítica de fluido y estructura. El cilindro de aluminio, que a su vez contiene aire a presión atmosférica y está rodeada de agua en alta presión, se modelando con elementos de lámina de tres nodos y sin grados de libertad de rotación. El cilindro se somete a deformaciones transitorias suficientemente rápidos y enormes hasta llegar a colapsar. Un nuevo modelo elástico de contacto sin considerar la fricción se ha desarrollado para detectar el contacto y calcular las fuerzas en el dominio discretizado entre las superficies medianas de las laminas. Dos esquemas temporales están considerados, uno es implícito utilizando el método de Bossak y otro es explícito utilizando Forward Euler. Al final los resultados de ambos casos se comparan con los resultados experimentales

    The development of efficient algorithms to understand implosion dynamics presents a number of challenges. The foremost challenge is to efficiently represent the coupled compressible fluid dynamics of internal air and surrounding water. Secondly, the method must allow one to accurately detect or follow the interface between the phases. Finally, it must be capable of resolving any shock waves which may be created in air or water during the final stage of the collapse. We present a fully Lagrangian compressible numerical framework for the simulation of underwater implosion. Both air and water are considered compressible and the equations for the Lagrangian shock hydrodynamics are stabilized via a variationally consistent multiscale method [109]. A nodally perfect matched definition of the interface is used [57, 25] and then the kinetic variables, pressure and density, are duplicated at the interface level. An adaptive mesh generation procedure, which respects the interface connectivities, is applied to provide enough refinement at the interface level. This framework is then used to simulate the underwater implosion of a large cylindrical bubble, with a size in the order of cm. Rapid collapse and growth of the bubble occurred on very small spatial (0.3mm), and time (0.1ms) scales followed by Rayleigh-Taylor instabilities at the interface, in addition to the shock waves traveling in the fluid domains are among the phenomena that are observed in the simulation. We then extend our framework to model the underwater implosion of a cylindrical aluminum container considering a monolithic fluid-structure interaction (FSI). The aluminum cylinder, which separates the internal atmospheric-pressure air from the external high-pressure water, is modeled by a three node rotation-free shell element. The cylinder undergoes fast transient deformations, large enough to produce self-contact along it. A novel elastic frictionless contact model is used to detect contact and compute the non-penetrating forces in the discretized domain between the mid-planes of the shell. Two schemes are tested, implicit using the predictor/multi-corrector Bossak scheme, and explicit, using the forward Euler scheme. The results of the two simulations are compared with experimental data.

    El desarrollo de métodos eficientes para modelar la dinámica de implosión presenta varios desafíos. El primero es una representación eficaz de la dinámica del sistema acoplado de aire-agua. El segundo es que el método tiene que permitir una detección exacta o un seguimiento adecuado de la interfase entre ambas fases. Por último el método tiene que ser capaz de resolver cualquier choque que podría generar en el aire o en el agua, sobre todo en la última fase del colapso. Nosotros presentamos un método numérico compresible y totalmente Lagrangiano para simular la implosión bajo el agua. Tanto el aire como el agua se consideran compresibles y las ecuaciones Lagrangianos para la hidrodinámica del choque se estabilizan mediante un método multiescala que es variacionalmente consistente [109]. Se utiliza una definición de interfase que coincide perfectamente con los nodos [57, 25]. Ésta, nos facilita duplicar eficazmente las variables cinéticas como la presión y la densidad en los nodos de la interfase. Con el fin de obtener suficiente resolución alrededor de la interfase, la malla se genera de forma adaptativa y respetando la posición de la interfase. A continuación el método desarrollado se utiliza para simular la implosión bajo el agua de una burbuja cilíndrica del tamaño de un centímetro. Varios fenómenos se han capturado durante el colapso: un ciclo inmediato de colapso-crecimiento de la burbuja que ocurre en un espacio (0.3mm) y tiempo (0.1ms) bastante limitado, aparición de inestabilidades de tipo Rayleigh-Taylor en la interfase y formaron de varias ondas de choque que viajan tanto en el agua como en el aire. Después, seguimos el desarrollo del método para modelar la implosión bajo el agua de un contenedor metálico considerando una interacción monolítica de fluido y estructura. El cilindro de aluminio, que a su vez contiene aire a presión atmosférica y está rodeada de agua en alta presión, se modelando con elementos de lámina de tres nodos y sin grados de libertad de rotación. El cilindro se somete a deformaciones transitorias suficientemente rápidos y enormes hasta llegar a colapsar. Un nuevo modelo elástico de contacto sin considerar la fricción se ha desarrollado para detectar el contacto y calcular las fuerzas en el dominio discretizado entre las superficies medianas de las laminas. Dos esquemas temporales están considerados, uno es implícito utilizando el método de Bossak y otro es explícito utilizando Forward Euler. Al final los resultados de ambos casos se comparan con los resultados experimentales.

  • ULITES - Ultra-lightweight structures with integrated photovoltaic solar cells: design, analysis, testing and application to an emergency shelter prototype

     Larese, Antonia; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    Participation in a competitive project

     Share

  • A coupled PFEM-Eulerian approach for the solution of porous FSI problems

     Larese, Antonia; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio; Idelsohn Barg, Sergio Rodolfo
    Computational Mechanics
    Date of publication: 2012-12
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Lock-in and drag amplification effects in slender line-like structures through CFD

     Vasallo Belver, Alí; Lorenzana Iban, Antolin; Rossi, Riccardo
    Wind and Structures
    Date of publication: 2012-05
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Lock-in and drag amplification phenomena are studied for a flexible cantilever using a simplified fluid-structure interaction approach. Instead of solving the 3D domain, a simplified setup is devised, in which 2D flow problems are solved on a number of planes parallel to the wind direction and transversal to the structure. On such planes, the incompressible Navier-Stokes equations are solved to estimate the fluid action at different positions of the line-like structure. The fluid flow on each plane is coupled with the structural deformation at the corresponding position, affecting the dynamic behaviour of the system. An Arbitrary Lagrangian-Eulerian (ALE) approach is used to take in account the deformation of the domain, and a fractional-step scheme is used to solve the fluid field. The stabilization of incompressibility and convection is achieved through orthogonal quasi-static subscales, an approach that is believed to provide a first step towards turbulence modelling. In order to model the structural problem, a special one-dimensional element for thin walled cross-section beam is implemented. The standard secondorder Bossak method is used for the time integration of the structural problem.

  • An algorithm for the simulation of thermally coupled low speed flow problems

     Ryzhakov, Pavel; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    International journal for numerical methods in fluids
    Date of publication: 2012-09
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • OpenCL-based implementation of an unstructured edge-based finite element convection-diffusion solver on graphics hardware

     Mossaiby, Farshid; Rossi, Riccardo; Dadvand, Pooyan; Idelsohn Barg, Sergio Rodolfo
    International journal for numerical methods in engineering
    Date of publication: 2012-03
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • A 1D lumped-parameter/3D CFD approach for pressure drop in the aortic coarctation

     Soudah Prieto, Eduardo; Bordoné, Maurizio; Dadvand, Pooyan; Rossi, Riccardo
    International Workshop on Statistical Atlases and Computational Models of the Heart
    Presentation's date: 2012-10
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Aortic Coarctation is a congenital constriction of the aorta that increases blood pressure above the constriction and hinders the flow below it. Based on a 3D surface mesh of a moderate thoracic coarctation, a high quality volume mesh is created using an optimal tetrahedral aspect ratio for whole domain. In order to quantify the severity of this constriction, a coupled 1D lumped-parameter/3D CFD approach is used to calculate the pressure drop through the coarctation. The CFD computation is performed assuming that the arterial wall is rigid and the blood is considered a homogeneous Newtonian fluid with density r = 0.001 gr/mm3 and a dynamic viscosity m = 0.004 gr/mm/sec in laminar flow. The boundary conditions of the 3D model (inlet and outlet conditions) have been calculated using a 1D model. Parallelization procedures will be used in order to increase the performance of the CFD calculations

    Aortic Coarctation is a congenital constriction of the aorta that increases blood pressure above the constriction and hinders the flow below it. Based on a 3D surface mesh of a moderate thoracic coarctation, a high quality volume mesh is created using an optimal tetrahedral aspect ratio for whole domain. In order to quantify the severity of this constriction, a coupled 1D lumped-parameter/3D CFD approach is used to calculate the pressure drop through the coarctation. The CFD computation is performed assuming that the arterial wall is rigid and the blood is considered a homogeneous Newtonian fluid with density r = 0.001 gr/mm3 and a dynamic viscosity m = 0.004 gr/mm/sec in laminar flow. The boundary conditions of the 3D model (inlet and outlet conditions) have been calculated using a 1D model. Parallelization procedures will be used in order to increase the performance of the CFD calculations.

  • Failure of rockfill dams during overtopping scenarios: a coupled level set-PFEM approach

     Larese, Antonia; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    European Congress on Computational Methods in Applied Sciences and Engineering
    Presentation's date: 2012-09
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Access to the full text
    A coupled Eulerian-PFEM model for the simulation of overtopping in rockfill dams  Open access

     Larese, Antonia; Oñate Ibáñez de Navarra, Eugenio; Rossi, Riccardo
    Date of publication: 2012
    Book

    Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

  • A coupled Eulerian-PFEM model for the simulation of overtopping in rockfill dams  Open access

     Larese, Antonia
    Defense's date: 2012-07-05
    Department of Strength of Materials and Structural Engineering, Universitat Politècnica de Catalunya
    Theses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    Rockfill dams are nowadays often preferred over concrete dams because of their economic advantages, their flexible design and thank to the great advance achieved in geosciences and geomechanics. Unfortunately their behavior in case of overtopping is still an open issue. In fact very little is known on this phenomenon that in most cases leads to the complete failure of the structure with catastrophic consequences in term of loss of lives and economic damage. The principal aim of the present thesis is the development of a computational method to simulate the overtopping and the beginning of failure of the downstream shoulder of a rockfill dam. The whole phenomenon is treated in a continuous framework. The fluid free surface problem outside and inside the rockfill slope is treated using a unique Eulerian fixed mesh formulation. A level set technique is employed to track the evolution of the free surface. The traditional Navier-Stokes equations are modified in order to automatically detect the presence of the porous media. The non-linear seepage is evaluated using a quadratic form of the resistance law for which the Ergun's coefficients have been chosen. The structural response of the solid skeleton is evaluated using a continuum viscous model. A non-Newtonian modified Bingham law is proposed for the simulation of the behaviour of a granular non-cohesive material. This approach has the possibility of considering a pressure sensitive resistance criteria. This is obtained inserting a Mohr-Coulomb failure criterion in the Bingham relation. Due to the large deformation of the mesh during the failure process, a Lagrangian framework is preferred to a fixed mesh one: the Particle Finite Element Method (PFEM) is therefore used. Its specific features make it appropriate to treat the rockfill material and its large deformations and shape changes. Finally a tool for mapping variables between non-matching meshes is developed to allow passing information between the fluid fixed and the dam moving meshes. All the numerical results are compared with experiments on prototype rockfill dams.

  • Improving mass conservation in simulation of incompressible flows

     Ryzhakov, Pavel; Oñate Ibáñez de Navarra, Eugenio; Rossi, Riccardo; Idelsohn Barg, Sergio Rodolfo
    International journal for numerical methods in engineering
    Date of publication: 2011-10-30
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Improving a strongly coupled method for FSI by a simple approximation of the pressure tangent matrix

     Rossi, Riccardo; Idelsohn Barg, Sergio Rodolfo; Oñate Ibáñez de Navarra, Eugenio; Cotela Dalmau, Jordi; Del Pin, Facundo
    Revista internacional de métodos numéricos para cálculo y diseño en ingeniería
    Date of publication: 2011
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Mejora de la solución fuertemente acoplada de problemas FSI mediante una aproximación de la matriz tangente de presión

     Rossi, Riccardo; Idelsohn Barg, Sergio Rodolfo; Oñate Ibáñez de Navarra, Eugenio; Cotela Dalmau, Jordi; Del Pin, Facundo
    Revista internacional de métodos numéricos para cálculo y diseño en ingeniería
    Date of publication: 2011
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Advances in the particle finite element method (PFEM) for solving coupled problems in engineering

     Oñate Ibáñez de Navarra, Eugenio; Idelsohn Barg, Sergio Rodolfo; Celigueta Jordana, Miguel Angel; Rossi, Riccardo; Marti, J.; Carbonell, J.Mª; Ryzhakov, Pavel; Suarez Arroyo, Benjamin
    Date of publication: 2011
    Book chapter

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    We present some developments in the formulation of the Particle Finite Element Method (PFEM) for analysis of complex coupled problems on fluid and solid mechanics in engineering accounting for fluid-structure interaction and coupled thermal effects, material degradation and surface wear. The PFEM uses an updated Lagrangian description to model the motion of nodes (particles) in both the fluid and the structure domains. Nodes are viewed as material points which can freely move and even separate from the main analysis domain representing, for instance, the effect of water drops. A mesh connects the nodes defining the discretized domain where the governing equations are solved, as in the standard FEM. The necessary stabilization for dealing with the incompressibility of the fluid is introduced via the finite calculus (FIC) method. An incremental iterative scheme for the solution of the non linear transient coupled fluid-structure problem is described. The procedure for modelling frictional contact conditions at fluid-solid and solid-solid interfaces via mesh generation are described. A simple algorithm to treat soil erosion in fluid beds is presented. An straight forward extension of the PFEM to model excavation processes and wear of rock cutting tools is described. Examples of application of the PFEM to solve a wide number of coupled problems in engineering such as the effect of large waves on breakwaters and bridges, the large motions of floating and submerged bodies, bed erosion in open channel flows, the wear of rock cutting tools during excavation and tunneling and the melting, dripping and burning of polymers in fire situations are presented.

  • Estudio de la capacidad de desagüe de aliviaderos con compuertas mediante modelación numérica: aplicación a la presa de Oliana

     Salazar González, Fernando; Rossi, Riccardo; Morán Moya, Rafael; Larese, Antonia
    Jornadas de Ingeniería del Agua
    Presentation's date: 2011-10
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Las curvas de desagüe de aliviaderos con compuertas, que permiten conocer el caudal que se está vertiendo en unas condiciones (nivel de embalse, apertura de compuerta) determinadas, suelen calcularse en base a formulaciones empíricas. La más utilizada, que es también la que recomienda la Guía Técnica de Seguridad de Presas nº 5 [1], es la desarrollada por el USACE [2]. Se basa en una campaña de ensayos en laboratorio a partir de la cual se obtuvo una curva que permite calcular el coeficiente de desagüe en función de la posición de la compuerta. Esta formulación no tiene en cuenta (se indica explícitamente) el efecto de contracción de la lámina, que depende de la relación entre el ancho de vano y la altura de lámina vertiente. Por tanto, debe considerarse como una primera aproximación a cada caso particular. Como consecuencia de ello, resulta necesario realizar campañas de ensayos en laboratorio específicas para cada nuevo aliviadero que se proyecta. En el presente trabajo se estudia la capacidad de desagüe de aliviaderos con compuertas radiales mediante la aplicación de un código de cálculo numérico al caso del aliviadero de la presa de Oliana. La presa de Oliana [5] es una presa de gravedad de hormigón, situada sobre el cauce del río Segre entre los términos municipales de Oliana y Peramola. Tiene una altura total desde cimientos de 102 m y su coronación, situada a la cota 519,60, tiene una longitud de 268 m. Su planta es curva, pero su talud es de 0,87 H: 1,0 V, por lo que está diseñada para resistir por gravedad. Tiene un aliviadero de superficie, situado sobre la propia coronación de la presa. Consta de dos vanos de 17 m de ancho cada uno, que están controlados por sendas compuertas tipo Taintor. El canal de descarga se sitúa sobre el paramento de aguas abajo de la presa, si bien está retranqueado hacia aguas arriba, para reducir la altura de los muros cajeros.

  • Simulating complex problems in civil engineering: the particle finite element method and beyond

     Rossi, Riccardo; Larese, Antonia; Oñate Ibáñez de Navarra, Eugenio; Idelsohn Barg, Sergio Rodolfo
    Congreso en Métodos Numéricos em Engenharia
    Presentation's date: 2011-06-15
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Access to the full text
    A modified fractional step approach  Open access

     Ryzhakov, Pavel; Oñate Ibáñez de Navarra, Eugenio; Rossi, Riccardo
    International Conference on Computer Methods in Mechanics
    Presentation's date: 2011-05
    Presentation of work at congresses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    We propose here a methodology for improving mass-conservation features of the fractional-step schemes on moving grids applied to viscous incompressible flows containing free surfaces. The idea is to find a better approximation for the intermediate velocity. This is achieved by using a prediction upon the end-of-step pressure in the pressure gradient term of the fractional momentum equation. Thus, an intermediate velocity results being much closer to the final one, than that of the standard fractional step scheme. We propose a methodology, where this goal can be achieved without necessitating to resolve any additional linear system.

  • A visco-rigid model using PFEM for simulating the failure of non-coheisve granular material

     Larese, Antonia; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    International Conference on Particle-Based Methods
    Presentation's date: 2011-10-27
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Theme B: simulation of the behavior of prototypes of rockfill dams during overtopping scenarios: seepage evolution and beginning of failure

     Larese, Antonia; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio; Toledo Municio, Miguel Ángel; Morán Moya, Rafael; Campos, Hibber; LARA, ÁNGEL; VIÑA, Mª DEL PILAR
    Benchmark Workshop on Numerical Analysis of Dams
    Presentation's date: 2011-10
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    In recent years the technology on embankments dams has developed sensibly due to the advances in soil mechanic, and in all related sciences. Nevertheless their vulnerability to overtopping still remains their weakest point in comparison with concrete structures. The principal aim of this theme is the simulation of the initial stage of failure of the dam when an overtopping or an exceptional flood occurs. A fluid-structure coupled problem has to be considered. The sudden variation of the upstream conditions induces a quick evolution of a seepage line in the downstream shoulder. Non linear Darcy law has to be taken into account. On the other hand the water, emerging from the toe of the dam, induces dragging of particles and possible mass sliding, depending on geometrical and material conditions. UPM and CEDEX have carried out more than 70 experiments during the last two years. They analyzed the influence of a series of parameters on the failure mechanisms. These parameters are, for instance, the dimension of the rocks, the slope of the downstream part of the dam, the type of impermeable element used, and so on. We propose to reproduce numerically three experiments analyzing the evolution of seepage and following initial stage of failure in the case of a homogeneous dam, of a dam with impermeable upstream face and of a dam with internal core. Experimental data, bottom pressure distribution and topographic analysis of the geometry of the dam during the failure can be compared with numerical results.

  • On the simulation of rock-fill dam behaviour in overspill conditions

     Rossi, Riccardo; Larese, Antonia; Oñate Ibáñez de Navarra, Eugenio
    Multiphysics
    Presentation's date: 2011-12-16
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • A combined PFEM-level set model to simulate the behavior of a rockfill dam in overtopping scenarios

     Larese, Antonia; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    International Conference on Computational Methods for Coupled Problems in Science and Engineering
    Presentation's date: 2011-06-22
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Access to the full text
    Scalable system for large unstructured mesh simulation  Open access

     Pasenau, Miguel; Dadvand, Pooyan; Rossi, Riccardo; Cotela Dalmau, Jordi; Coll, Abel; Oñate Ibáñez de Navarra, Eugenio
    International Conference on Parallel Computational Fluid Dynamics
    Presentation's date: 2011-05
    Presentation of work at congresses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    Dealing with large simulation is a growing challenge. Ideally for the wellparallelized software prepared for high performance, the problem solving capability depends on the available hardware resources. But in practice there are several technical details which reduce the scalability of the system and prevent the effective use of such a software for large problems. In this work we describe solutions implemented in order to obtain a scalable system to solve and visualize large scale problems. The present work is based on Kratos MutliPhysics [1] framework in combination with GiD [2] pre and post processor. The applied techniques are verified by CFD simulation and visualization of a wind tunnel problem with more than 100 millions of elements in our in-hose cluster in CIMNE.

  • Numerical modeling of the hydraulic performance of Oliana dam spillway using Kratos

     Salazar González, Fernando; Morán Moya, Rafael; Rossi, Riccardo; Larese, Antonia
    Benchmark Workshop on Numerical Analysis of Dams
    Presentation's date: 2011-10-21
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Head-discharge curves in gated spillways are commonly obtained by means of the application of empirical formulations. The most popular one, recommended by SPANCOLD [1], was developed by the U.S. Army Corps of Engineers [2]. It is based in several experimental campaigns whose results were used to define a chart which provides the value of the discharge coefficient depending on the gate position. This formula does not take into account the effect of side contractions, which depends on the length-height ratio of the bays, as well as the head, the inflow conditions and spillway geometry. Thus, it is necessary to carry out specific experimental tests for every new spillway. The aim of the work is the analysis of the discharge capacity of radial gated spillways. The accuracy of empirical formulations has been studied, and Oliana Dam spillway has been investigated via numerical simulation.

  • Aeroelastic analysis of inflatable low-pressure tubular pavillons with the FEM

     Dadvand, Pooyan; Solina, M.; Oñate Ibáñez de Navarra, Eugenio; Rossi, Riccardo
    International Conference on Textile Composites and Inflatable Structures
    Presentation's date: 2011-10-06
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Coupling eulerian and lagrangian models to simulate seepage and evolution of failure in prototype rockfill dams

     Larese, Antonia; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    Benchmark Workshop on Numerical Analysis of Dams
    Presentation's date: 2011-10
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    This work presents a model which allows considering the interaction between rockfill dams and the water. The fluid behaviour is analyzed on an Eulerian fixed mesh. A level set technique is employed to tack the evolution of the free surface. An edge based approach is used to solve efficiently the modified form of the Navier‐Stokes equations. The dam response is evaluated on a Lagrangian moving mesh using PFEM. A visco‐rigid constitutive model is used to describe the structural behaviour and collapse of rockfill under fluid dynamic forces. Mohr‐Coulomb is the failure criteria adopted in the calculation. Finally a nodal projection algorithm allows the transferring of information through non matching meshes.

  • Access to the full text
    Migration of a generic multi-physics framework to HPC environments  Open access

     Dadvand, Pooyan; Rossi, Riccardo; Gil Gómez, Maria Luisa; Martorell Bofill, Xavier; Cotela Dalmau, Jordi; Juanpere Cañameras, Edgar; Idelsohn Barg, Sergio Rodolfo; Oñate Ibáñez de Navarra, Eugenio
    International Conference on Parallel Computational Fluid Dynamics
    Presentation's date: 2011-05-17
    Presentation of work at congresses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    Creating a highly parallelizable code is a challenge and development for distributed memory machines (DMMs) can be very different form developing a serial code in term of algorithms and structure. For this reason, many developers in the field prefer to develop their own code from scratch. However, for an already existing framework with large development background the idea of transformation becomes attractive in order to reuse the effort done during years of development. In this presentation we explain how a relatively complex framework but with modular structure can be prepared for high performance computing with minimum modification. Kratos Multi-Physics [1] is an open source generic multi-disciplinary platform for solution of coupled problems consist of fluid, structure, thermal and electromagnetic fields. The parallelization of this framework is performed with objective of enforcing the less possible changes to its different solver modules and encapsulate the changes as much as possible in its common kernel. This objective is achieved thanks to the Kratos design and also innovative way of dealing with data transfers for a multi-disciplinary code. This work is completed by the migration of the framework from the x86 architecture to the Marenostrum Supercomputing platform. The migration has been verified by a set of benchmarks which show very good scalability, from which we present the Telescope problem in this paper.

  • Desarrollo de Herramientas para el Análisis de Estabilidad en Laderas con Riesgo Potencial sobre Infraestructuras

     Rossi, Riccardo; Salazar González, Fernando
    Participation in a competitive project

     Share

  • An object-oriented environment for developing finite element codes for multi-disciplinary applications

     Dadvand, Pooyan; Rossi, Riccardo; Oñate Ibáñez de Navarra, Eugenio
    Archives of computational methods in engineering
    Date of publication: 2010-09
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window