ANTONIO J. GIL H. - Academia.edu (original) (raw)

Papers by ANTONIO J. GIL H.

Research paper thumbnail of A first order hyperbolic framework for large strain computational solid dynamics. Part I: Total Lagrangian isothermal elasticity

This paper introduces a new computational framework for the analysis of large strain fast solid d... more This paper introduces a new computational framework for the analysis of large strain fast solid dynamics. The paper builds upon previous work published by the authors (Gil et al., 2014) [1], where a first order system of hyperbolic equations is introduced for the simulation of isothermal elastic materials in terms of the linear momentum, the deformation gradient and its Jacobian as unknown variables. In this work, the formulation is further enhanced with four key novelties. First, the use of a new geometric conservation law for the co-factor of the deformation leads to an enhanced mixed formulation, advantageous in those scenarios where the co-factor plays a dominant role. Second, the use of polyconvex strain energy functionals enables the definition of generalised convex entropy functions and associated entropy fluxes for solid dynamics problems. Moreover, the introduction of suitable conjugate entropy variables enables the derivation of a symmetric system of hyperbolic equations, dual of that expressed in terms of conservation variables. Third, the use of a new tensor cross product greatly facilitates the algebraic manipulations of expressions involving the co-factor of the deformation. Fourth, the development of a stabilised Petrov-Galerkin framework is presented for both systems of hyperbolic equations, that is, when expressed in terms of either conservation or entropy variables. As an example, a polyconvex Mooney

Research paper thumbnail of An upwind vertex centred Finite Volume solver for Lagrangian solid dynamics

Journal of Computational Physics, 2015

A vertex centred Jameson-Schmidt-Turkel (JST) finite volume algorithm was recently introduced by ... more A vertex centred Jameson-Schmidt-Turkel (JST) finite volume algorithm was recently introduced by the authors (Aguirre et al., 2014 [1]) in the context of fast solid isothermal dynamics. The spatial discretisation scheme was constructed upon a Lagrangian two-field mixed (linear momentum and the deformation gradient) formulation presented as a system of conservation laws [2-4]. In this paper, the formulation is further enhanced by introducing a novel upwind vertex centred finite volume algorithm with three key novelties. First, a conservation law for the volume map is incorporated into the existing two-field system to extend the range of applications towards the incompressibility limit (Gil et al., 2014 [5]). Second, the use of a linearised Riemann solver and reconstruction limiters is derived for the stabilisation of the scheme together with an efficient edge-based implementation. Third, the treatment of thermo-mechanical processes through a Mie-Grüneisen equation of state is incorporated in the proposed formulation. For completeness, the study of the eigenvalue structure of the resulting system of conservation laws is carried out to demonstrate hyperbolicity and obtain the correct time step bounds for non-isothermal processes. A series of numerical examples are presented in order to assess the robustness of the proposed methodology. The overall scheme shows excellent behaviour in shock and bending dominated nearly incompressible scenarios without spurious pressure oscillations, yielding second order of convergence for both velocities and stresses.

Research paper thumbnail of Editorial for Computers and Structures

Computers & Structures, 2017

The UK Association of Computational Mechanics (UK-ACM) (http://ukacm.org/) was founded in March 1... more The UK Association of Computational Mechanics (UK-ACM) (http://ukacm.org/) was founded in March 1992 with the purpose of promoting research in Computational Mechanics in the UK and establishing formal links with similar organisations across Europe and worldwide. The Association is affiliated with the European Community of Computational Methods in Applied Sciences (ECCOMAS) and the International Association for Computational Mechanics (IACM). The principal activity of UK-ACM involves the organisation of an annual two-day Conference focussed on the latest developments and research trends in the field of Computational Mechanics. The Conference is particularly orientated towards encouraging young scientists in the field to present their current research at both Doctoral and Post-Doctoral levels. The Conference is therefore a unique forum to foster ideas, enable new multidisciplinary research approaches and establish collaborative research links, helping to build strong research networks within the UK and at an international level.

Research paper thumbnail of A first order hyperbolic framework for large strain computational solid dynamics. Part I: Total Lagrangian isothermal elasticity

This paper introduces a new computational framework for the analysis of large strain fast solid d... more This paper introduces a new computational framework for the analysis of large strain fast solid dynamics. The paper builds upon previous work published by the authors (Gil et al., 2014) [1], where a first order system of hyperbolic equations is introduced for the simulation of isothermal elastic materials in terms of the linear momentum, the deformation gradient and its Jacobian as unknown variables. In this work, the formulation is further enhanced with four key novelties. First, the use of a new geometric conservation law for the co-factor of the deformation leads to an enhanced mixed formulation, advantageous in those scenarios where the co-factor plays a dominant role. Second, the use of polyconvex strain energy functionals enables the definition of generalised convex entropy functions and associated entropy fluxes for solid dynamics problems. Moreover, the introduction of suitable conjugate entropy variables enables the derivation of a symmetric system of hyperbolic equations, dual of that expressed in terms of conservation variables. Third, the use of a new tensor cross product greatly facilitates the algebraic manipulations of expressions involving the co-factor of the deformation. Fourth, the development of a stabilised Petrov-Galerkin framework is presented for both systems of hyperbolic equations, that is, when expressed in terms of either conservation or entropy variables. As an example, a polyconvex Mooney

Research paper thumbnail of An upwind vertex centred Finite Volume solver for Lagrangian solid dynamics

Journal of Computational Physics, 2015

A vertex centred Jameson-Schmidt-Turkel (JST) finite volume algorithm was recently introduced by ... more A vertex centred Jameson-Schmidt-Turkel (JST) finite volume algorithm was recently introduced by the authors (Aguirre et al., 2014 [1]) in the context of fast solid isothermal dynamics. The spatial discretisation scheme was constructed upon a Lagrangian two-field mixed (linear momentum and the deformation gradient) formulation presented as a system of conservation laws [2-4]. In this paper, the formulation is further enhanced by introducing a novel upwind vertex centred finite volume algorithm with three key novelties. First, a conservation law for the volume map is incorporated into the existing two-field system to extend the range of applications towards the incompressibility limit (Gil et al., 2014 [5]). Second, the use of a linearised Riemann solver and reconstruction limiters is derived for the stabilisation of the scheme together with an efficient edge-based implementation. Third, the treatment of thermo-mechanical processes through a Mie-Grüneisen equation of state is incorporated in the proposed formulation. For completeness, the study of the eigenvalue structure of the resulting system of conservation laws is carried out to demonstrate hyperbolicity and obtain the correct time step bounds for non-isothermal processes. A series of numerical examples are presented in order to assess the robustness of the proposed methodology. The overall scheme shows excellent behaviour in shock and bending dominated nearly incompressible scenarios without spurious pressure oscillations, yielding second order of convergence for both velocities and stresses.

Research paper thumbnail of Editorial for Computers and Structures

Computers & Structures, 2017

The UK Association of Computational Mechanics (UK-ACM) (http://ukacm.org/) was founded in March 1... more The UK Association of Computational Mechanics (UK-ACM) (http://ukacm.org/) was founded in March 1992 with the purpose of promoting research in Computational Mechanics in the UK and establishing formal links with similar organisations across Europe and worldwide. The Association is affiliated with the European Community of Computational Methods in Applied Sciences (ECCOMAS) and the International Association for Computational Mechanics (IACM). The principal activity of UK-ACM involves the organisation of an annual two-day Conference focussed on the latest developments and research trends in the field of Computational Mechanics. The Conference is particularly orientated towards encouraging young scientists in the field to present their current research at both Doctoral and Post-Doctoral levels. The Conference is therefore a unique forum to foster ideas, enable new multidisciplinary research approaches and establish collaborative research links, helping to build strong research networks within the UK and at an international level.