Documents published in Scipedia

• Modeling incompressible flows at low and high Reynolds numbers via a finite calculus–finite element approach

  E. Oñate, A. Valls, J. García-Espinosa

  Journal of Computational Physics (2007). 224 (1), 332-351

  
  

  Abstract

  We present a formulation for incompressible flows analysis using the finite element method (FEM). The necessary stabilization for dealing with convective effects and the incompressibility condition is modeled via the finite calculus (FIC) method. The stabilization terms introduced by the FIC formulation allow to solve a wide range of fluid flow problems for low and high Reynolds numbers flows without the need for a turbulence model. Examples of application of the FIC/FEM formulation to the analysis of 2D and 3D incompressible flows with moderate and large Reynolds numbers are presented.

  Abstract
  We present a formulation for incompressible flows analysis using the finite element method (FEM). The necessary stabilization for dealing with convective effects and the [...]

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• Finite calculus formulations for finite element analysis of incompressible flows. Eulerian, ALE and Lagrangian approaches

  E. Oñate, J. García-Espinosa, S. Idelsohn, F. Pin

  Computer methods in applied mechanics and engineering (2006). 195 (23), 3001-3037

  
  

  Abstract

  We present a general formulation for incompressible fluid flow analysis using the finite element method (FEM). The standard Eulerian formulation is described first. The necessary stabilization for dealing with convective effects and the incompressibility condition are introduced via the finite calculus (FIC) method. A simple extension of the fluid flow equations to an arbitrary Lagrangian–Eulerian (ALE) frame adequate for treating fluid–structure interaction problems is briefly presented. A fully Lagrangian formulation called the particle finite element method (PFEM) is also described. The PFEM is particularly attractive for fluid–structure interaction problems involving large motions of the free surface and breaking waves. Examples of application of the Eulerian, the ALE and the fully lagrangian PFEM formulations are presented.

  Abstract
  We present a general formulation for incompressible fluid flow analysis using the finite element method (FEM). The standard Eulerian formulation is described first. The [...]

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• An unstructured finite element solver for ship hydrodynamics problems

  J. García-Espinosa, E. Oñate

  Journal of Applied Mechanics (2003). 70(1): 18-26

  
  

  Abstract

  A stabilized semi-implicit fractional step algorithm based on the finite element method for solving ship wave problems using unstructured meshes is presented. The stabilized gov-erning equations for the viscous incompressible fluid and the free surface are derived at a differential level via a finite calculus procedure. This allows us to obtain a stabilized numerical solution scheme. Some particular aspects of the problem solution, such as the mesh updating procedure and the transom stern treatment, are presented. Examples of the efficiency of the semi-implicit algorithm for the analysis of ship hydrodynamics problems are presented.

  Abstract
  A stabilized semi-implicit fractional step algorithm based on the finite element method for solving ship wave problems using unstructured meshes is presented. The stabilized [...]

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• A finite element method for fluid-structure interaction with surface waves using a finite calculus formulation

  E. Oñate, J. García-Espinosa

  Comput. Methods Appl. Mech. Engrg. (2001). 191, 635-660

  
  

  Abstract

  A stabilized semi-implicit fractional step finite element method (FEM) for solving coupled fluid-structure interaction problems involving free surface waves is presented. The stabilized governing equations for the viscous incompressible fluid and the free surface are derived at a differential level via a finite calculus (FIC) procedure. A mesh updating technique based on solving a fictitious elastic problem on the moving mesh is described. Examples of the efficiency of the stabilized semi-implicit algorithm for the analysis of fluid-structure interaction problems in totally or partially submerged bodies is presented.

  Abstract
  A stabilized semi-implicit fractional step finite element method (FEM) for solving coupled fluid-structure interaction problems involving free surface waves is presented. [...]

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• A family of residual‐based stabilized finite element methods for Stokes flows

  E. Oñate, P. Nadukandi, S. Idelsohn, J. García-Espinosa, C. Felippa

  Int. J. Numer. Meth. Fluids (2011). Vol. 65 (1-3), pp. 106-134

  
  

  Abstract

  We present a collection of stabilized finite element (FE) methods derived via first‐ and second‐order finite calculus (FIC) procedures. It is shown that several well known existing stabilized FE methods such as the penalty technique, the Galerkin Least Square (GLS) method, the Pressure Gradient Projection (PGP) method and the orthogonal sub‐scales (OSS) method are recovered from the general residual‐based FIC stabilized form. A new family of stabilized Pressure Laplacian Stabilization (PLS) FE methods with consistent nonlinear forms of the stabilization parameters are derived. The distinct feature of the family of PLS methods is that they are residual‐based, i.e. the stabilization terms depend on the discrete residuals of the momentum and/or the incompressibility equations. The advantages and disadvantages of the different stabilization techniques are discussed and several examples of application are presented.

  Abstract
  We present a collection of stabilized finite element (FE) methods derived via first‐ and second‐order finite calculus (FIC) procedures. It is shown that several well known [...]

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• Un método de elementos finitos para análisis hidrodinámico de estructuras navales

  J. García-Espinosa, E. Oñate, H. Sierra

  Monograph CIMNE (2000). M59

  
  

  Abstract

  En este trabajo se presenta una metodología basada en el método de los elementos finitos para el análisis de problemas de flujo incompresible en fluidodinámica naval. Esta metodología se basa en la obtención de unas nuevas ecuaciones diferenciales, basadas en criterios discretos, alternativas a las tradicionales ecuaciones de Navier-Stokes. El punto más novedoso del presente trabajo es la aplicación del método de análisis de flujo incomprensible mencionado a problemas navales.

  Abstract
  En este trabajo se presenta una metodología basada en el método de los elementos finitos para el análisis de problemas de flujo incompresible en fluidodinámica [...]

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• Computation of the stabilization parameter for the finite element solution of advective–diffusive problems

  E. Oñate, J. García-Espinosa, S. Idelsohn

  Int. J. for Num. Meths. in Fluids (1997). Vol. 25, pp. 1387-1407

  
  

  Abstract

  In a previous paper a general procedure for deriving stabilized finite element schemes for advective type problems based on invoking higher order balance laws over finite size domains was presented. This provides an expression for the element stabilization parameter in terms of the solution residual and its first derivatives in a kind of iterative or adaptative manner. Details of the application of this procedure to 1D and 2D advective- diffusive problems are given. Some examples of applications showing the potential of the new approach are presented. 

  Abstract
  In a previous paper a general procedure for deriving stabilized finite element schemes for advective type problems based on invoking higher order balance laws over finite [...]

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• FIC/FEM Formulation with Matrix Stabilizing Terms for Incompressible Flows at Low and High Reynolds Numbers

  E. Oñate, A. Valls, J. García-Espinosa

  Computational Mechanics (2006). Vol. 38 (4-5), pp. 440-455

  
  

  Abstract

  We present a general formulation for incompressible fluid flow analysis using the finite element method. The necessary stabilization for dealing with convective effects and the incompressibility condition are introduced via the Finite Calculus method using a matrix form of the stabilization parameters. This allows to model a wide range of fluid flow problems for low and high Reynolds numbers flows without introducing a turbulence model. Examples of application to the analysis of incompressible flows with moderate and large Reynolds numbers are presented.

  Abstract
  We present a general formulation for incompressible fluid flow analysis using the finite element method. The necessary stabilization for dealing with convective effects and [...]

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• A Petrov–Galerkin formulation for the alpha interpolation of FEM and FDM stencils: Applications to the Helmholtz equation

  P. Nadukandi, E. Oñate, J. García-Espinosa

  Int. J. Numer. Meth. Engng. (2012). Vol. 89 (11), pp. 1367-1391

  
  

  Abstract

  A new Petrov–Galerkin (PG) method involving two parameters, namely α1 and α2, is presented, which yields the following schemes on rectangular meshes: (i) a compact stencil obtained by the linear interpolation of the Galerkin FEM and the classical central finite difference method (FDM), should the parameters be equal, that is, α1 = α2 = α; and (ii) the nonstandard compact stencil presented in (Int. J. Numer. Meth. Engng 2011; 86:18–46) for the Helmholtz equation if the parameters are distinct, that is, α1 ≠ α2. The nonstandard compact stencil is obtained by taking the linear interpolation of the diffusive terms (specified by α1) and the mass terms (specified by α2) that appear in the stencils obtained by the standard Galerkin FEM and the classical central FDM, respectively. On square meshes, these two schemes were shown to provide solutions to the Helmholtz equation that have a dispersion accuracy of fourth and sixth order, respectively (Int. J. Numer. Meth. Engng 2011; 86:18–46). The objective of this paper is to study the performance of this PG method for the Helmholtz equation using nonuniform meshes and the treatment of natural boundary conditions.

  Abstract
  A new Petrov–Galerkin (PG) method involving two parameters, namely α1 and α2, is presented, which yields the following schemes on rectangular [...]

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• A fourth‐order compact scheme for the Helmholtz equation: Alpha‐interpolation of FEM and FDM stencils

  P. Nadukandi, E. Oñate, J. García-Espinosa

  Int. J. Numer. Meth. Engng. (2011). Vol. 86 (1), pp. 18-46

  
  

  Abstract

  We propose a fourth‐order compact scheme on structured meshes for the Helmholtz equation given by R(φ):=f(x)+Δφ+ξ2φ=0. The scheme consists of taking the alpha‐interpolation of the Galerkin finite element method and the classical central finite difference method. In 1D, this scheme is identical to the alpha‐interpolation method (J. Comput. Appl. Math. 1982; 8(1):15–19) and in 2D making the choice α=0.5 we recover the generalized fourth‐order compact Padé approximation (J. Comput. Phys. 1995; 119:252–270; Comput. Meth. Appl. Mech. Engrg 1998; 163:343–358) (therein using the parameter γ=2). We follow (SIAM Rev. 2000; 42(3):451–484; Comput. Meth. Appl. Mech. Engrg 1995; 128:325–359) for the analysis of this scheme and its performance on square meshes is compared with that of the quasi‐stabilized FEM (Comput. Meth. Appl. Mech. Engrg 1995; 128:325–359). In particular, we show that the relative phase error of the numerical solution and the local truncation error of this scheme for plane wave solutions diminish at the rate O((ξℓ)4), where ξ, ℓ represent the wavenumber and the mesh size, respectively. An expression for the parameter α is given that minimizes the maximum relative phase error in a sense that will be explained in Section 4.5. Convergence studies of the error in the L2 norm, the H1 semi‐norm and the l∞ Euclidean norm are done and the pollution effect is found to be small. Copyright © 2010 John Wiley & Sons, Ltd.

  Abstract
  We propose a fourth‐order compact scheme on structured meshes for the Helmholtz equation given by R(φ):=f(x)+Δφ+ξ2φ=0. The scheme consists of taking [...]

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Articles (Documents not available in Scipedia)

• Estudio dinámico de líneas de fondeo en plataformas flotantes de aerogeneradores marinos

  J. García-Espinosa

  Ingeniería naval, 66-72, 2014

• Avances en el desarrollo de un modelo de elementos finitos para evaluación de un buque de efecto superficie

  J. García-Espinosa, B. Serván, D. Di Capua, P.A. Ubach, E. Oñate

  Ingeniería naval, 922: 68-73

• Estudio del Comportamiento Dinámico Acoplado en Estructuras Offshore

  JEG Romero, BZ Parra, JG Espinosa, JAE Pérez

  Anuario de Jóvenes Investigadores, 39-41, 2014

• Prediction of total resistance coefficients using neural networks

  I Ortigosa, R López, J García

  Journal of Maritime Research 6 (3), 15-26

• Dynamic modelling of mooring for floating offshore structures

  JE Gutiérrez Romero, B Zamora Parra, J García Espinosa, J Esteve

  Computational Methods in Marine Engineering V-Proceedings of the 5th ..., 2013

• Desarrollo de un conjunto de herramientas para el análisis acoplado de aerogeneradores en alta mar

  JE Gutiérrez Romero, B Zamora, J García Espinosa, J Esteve Pérez

  Ingeniería naval, 62-75, 2013

• Stabilized finite element methods for convection-diffusion-reaction, Helmholtz and Stokes problems

  P Nadukandi

  Universitat Politècnica de Catalunya, 2011

• A family of residual‐based stabilized finite element methods for Stokes flows

  E Oñate, P Nadukandi, SR Idelsohn, J García, C Felippa

  International Journal for Numerical Methods in Fluids 65 (1‐3), 106-134, 2011

• Experiencias en el desarrollo y aplicación de herramientas de cálculo y verificación de estructuras marinas para generación de energía

  J García Espinosa, B Serván Camas, D Sá

  49º Congreso de Ingeniería Naval e Industria Marítima, 1-16, 2010

• Análisis estructural del efecto de explosiones a bordo de buques de pasaje

  J García-Espinosa, D Di Capua, D Sá, S Honrubia, F Viejo, E Oñate, R Marí, ...

  Ingeniería naval, 105-114, 2007

• ODD Level Set: A new method for simulation of free surface problems

  JG Espinosa, AV Tomás

  Journal of maritime research 3 (1), 27-40, 2006

• Análisis CFD del movimiento de balance de un portacontenedores

  J García-Espinosa, E Oñate, JB Helmers, MR Chakkor

  Ingeniería Naval, abril, 2004

• Ship hydrodynamics

  E Onate, J García, SR Idelsohn

  Encyclopedia of computational mechanics, 2004

• A methodology for analysis of fluid-structure interaction accounting for free surface waves

  E Oñate, J García, S Idelsohn

  European Conference on Computational Mechanics (ECCM99), 1999

• A stabilized numerical method for analysis of ship hydrodynamics

  J García, E Oñate, H Sierra, C Sacco, S Idelsohn

  Computational fluid dynamics'98, 664-669, 1998

• An alpha-adaptive approach for stabilized finite element solution of advective-diffusive problems with sharp gradients

  E Onate, J García-Espinosa, S Idelsohn

  Computational fluid dynamics'98, 748-753, 1998

• On the stabilization of numerical solution for advective-diffusive transport and fluid flow problems

  E Oñate, J García, S Idelsohn

  Centro Internacional de Métodos Numéricos en Ingeniería, 1996

Books, book chapters and edited books (Documents not available in Scipedia)

• MARINE 2011, IV International Conferencn Marine Engineering: Selected Papers

  L. Eca, E. Oñate, J. García-Espinosa, T. Kvamsdal, P. Bergan

  Springer

• Fluid-Structure interaction applied to blood flow simulations

  E. Soudah, E. Oñate, J. García-Espinosa, J. S. Pérez, A. Mena, E. Heindenreich, J. F. Rodríguez, M. A. Martínez, M. Doblaré

  Advances in Computational Vision and Medical Image Processing, Springer

• Computational Methods in Marine Engineering III (MARINE 2009)

  P. Bergan, B. Pettersen, T. Kvamsdal, E. Oñate, J. García-Espinosa

  CIMNE

• Computational Methods in Marine Engineering II (MARINE 2007)

  P. Bergan, J. García-Espinosa, P. Kvamsdal, T. Kvamsdal, E. Oñate

  CIMNE

• LES turbulence models. Relation with stabilized numerical methods

  A. Valls, J. Garcia-Espinosa, E. Oñate

  Models, Experiments and Computation in Turbulence, CIMNE

• Computational Methods in Marine Engineering (MARINE 2005)

  P. Bergan, J. García-Espinosa, E. Oñate, T. Kvamsdal

  CIMNE

• A general stabilized formulation for incompressible fluid flow using finite calculus and the finite element method

  E. Onate, J. Garcia-Espinosa, G. Bugeda, S.R. Idelsohn

  Fluid dynamics and aeronautics new challenges: a book dedicated to Pierre Perrier. J. Periaux, D. Chamption, O. Pironneau, P.H. Thomas, eds.

Conference papers and presentations (Documents not available in Scipedia)

• A finite element method for fluid-structure interaction with surface waves

  J. Garcia-Espinosa and E. Oñate

  Proceedings of the European Conference on Computational Mechanics (ECCM 2001)

• Finite element analysis of incompressible flows with free surface waves using a finite calculus formulation

  E. Oñate, J. García-Espinosa

  Proceedings of the VI European Congress in Computational Methods in Applied Sciences and Engineering (ECCOMAS 2001)

Technical reports, thesis and other (Documents not available in Scipedia)

• Desarrollo de herramientas de autoaprendizaje multimedia para cálculo de estructuras por ordenador en ingeniería

  J. García-Espinosa, J. Martínez, D. Yebra, M. Cervera Ruiz, E. Oñate, S. Oller, B. Suárez

  Universitat Politècnica de Catalunya. Institut de Ciències de l'Educació, 2013