Listar por autor "Navarrina, Fermín"
Mostrando ítems 61-80 de 97
-
High order finite volume schemes on unstructured grids using Moving Least Squares reconstruction. Application to shallow water dynamics
Cueto-Felgueroso Landeira, Luis; Colominas, Ignasi; Navarrina, Fermín; Casteleiro, Manuel (John Wiley and Sons, 2005)[Abstract] This paper introduces the use of Moving Least Squares (MLS) approximations for the development of high-order finite volume discretizations on unstructured grids. The field variables and their succesive derivatives ... -
High Order Shape Design Sensitivity: A Unified Approach
Navarrina, Fermín; López Fontán, Santiago; Colominas, Ignasi; Bendito Pérez, Enrique; Casteleiro, Manuel (Elsevier, 2000)[Abstract] Three basic analytical approaches have been proposed for the calculation of sen- sitivity derivatives in shape optimization problems. The first approach is based on differentiation of the discretized equations ... -
High order shape design sensitivity: an unified approach
Navarrina, Fermín; López Fontán, Santiago; Colominas, Ignasi; Bendito Pérez, Enrique; Casteleiro, Manuel (Centro Internacional de Métodos Numéricos en Ingeniería, 1998)[Abstract] Three basic analytical approaches have been proposed for the calculation of sensitivity derivatives in shape optimization problems. The first approach is based on differentiation of the discretized equations. ... -
High performance computing for the analysis and postprocessing of earthing systems in layered soils
Colominas, Ignasi; Gómez Calviño, Javier; Navarrina, Fermín; Casteleiro, Manuel (2002)[Abstract] In this paper, we present a BEM formulation for the analysis and postprocessing of grounding systems embedded in layered soils, and we discuss the highligths of its implementation in a High-Performance Parallel ... -
Improved δ-SPH Scheme With Automatic and Adaptive Numerical Dissipation
Krimi, Abdelkader; Ramírez, Luis; Khelladi, Sofiane; Navarrina, Fermín; Deligant, Michaël; Nogueira, Xesús (MDPI, 2020)[Abstract] In this work we present a δ-Smoothed Particle Hydrodynamics (SPH) scheme for weakly compressible flows with automatic adaptive numerical dissipation. The resulting scheme is a meshless self-adaptive method, in ... -
Meshless methods applied to potential flow problems
Mosqueira Martínez, Gonzalo; Colominas, Ignasi; Navarrina, Fermín; Casteleiro, Manuel (Elsevier, 2001)[Abstract] In this paper we discuss some of the meshless approaches that have been recently proposed for solving boundary value problems. Several functional approximations and different integration schemes are studied. In ... -
Meshless methods for potential problems in electrical engineering applications
Colominas, Ignasi; Mosqueira Martínez, Gonzalo; Chao López, Mar; Navarrina, Fermín; Casteleiro, Manuel (Elsevier, 1999)[Abstract] In some problems in engineering applications, the mesh generation process represents one of the big challenges when numerical methods such as finite elements, finite differences or boundary elements are applied. ... -
Métodos numéricos de partículas para la simulación de problemas en dinámica de fluídos
Cueto-Felgueroso Landeira, Luis; Colominas, Ignasi; Mosqueira Martínez, Gonzalo; Navarrina, Fermín; Casteleiro, Manuel (2004)[Resumen] En este artículo se propone una formulación numérica sin malla de tipo Galerkin basada en el método de Smoothed Particle Hydrodynamics (SPH) con aproximación de mínimos cuadrados móviles, y su aplicación a ... -
Minimum weight with stress constraints topology optimization
Colominas, Ignasi; Muíños Pantín, Iago; Navarrina, Fermín; Casteleiro, Manuel (2003)[Abstract] Sizing and shape structural optimization problems are normally stated in terms of a minimum weight approach with constraints that limit the maximum allowable stresses and displacements. However, topology ... -
Modelización numérica de problemas de potenciales transferidos por redes de tierra mediante el método de los elementos de contorno
Colominas, Ignasi; Navarrina, Fermín; Casteleiro, Manuel (2004)[Resumen] El análisis y diseño de tomas de tierra en subestaciones eléctricas requiere el cálculo de la distribución de los niveles de potencial sobre la superficie del terreno y la resistencia equivalente de la red de ... -
Modelling Free-surface flows by a Galerkin based SPH formulation
Cueto-Felgueroso Landeira, Luis; Colominas, Ignasi; Mosqueira Martínez, Gonzalo; Navarrina, Fermín; Casteleiro, Manuel (2003)[Abastract] An algorithm based on Moving Least Squares Particle Hydrodynamics (MLSPH) to solve free surface flow is presented. MLS shape functions remarkably improve stability and accuracy of standard SPH algorithms, ... -
Una nueva formulación de elementos finitos para la optimización topológica de estructuras basada en la minización del peso con restricciones en tensión
París, José; Navarrina, Fermín; Colominas, Ignasi; Casteleiro, Manuel (2005)En este artículo se presenta una nueva formulación de Elementos Finitos para la Optimización Topológica de Estructuras. Los modelos tradicionalmente propuestos hasta el momento se basan en optimizar la distribución de ... -
Numerical Analysis and Safety Design of Grounding Systems in Underground Compact Substations
Guizán Roca, Raquel; Colominas, Ignasi; París, José; Couceiro, Iván; Navarrina, Fermín (Elsevier, 2022)[Abstract] This paper presents a mathematical and numerical formulation to design and analyze grounding systems in underground electrical substations. The developed approach is based on the well known Maxwell’s Equations. ... -
Numerical approaches for grounding installations in uniform and stratified soils
Colominas, Ignasi; Gómez Calviño, Javier; Mosqueira Martínez, Gonzalo; Navarrina, Fermín; Casteleiro, Manuel (2002)[Abstract] This paper summarizes the main numerical approaches based on the BEM developed by the authors in the last years for the grounding analysis of electrical installations in uniform and layered soils. -
Numerical computation of grounding grids
Colominas, Ignasi; Navarrina, Fermín; Casteleiro, Manuel (Asociación Argentina de Mecánica Computacional, 1995)[Abstract] Grounding systems are designed to preserve human safety and grant the integrity of equipments under fault conditions. To achieve these goals, the equivalent electrical resistance of the system must be low ... -
Numerical modelling for grounding grids in high-performance parallel computers
Colominas, Ignasi; Navarrina, Fermín; Mosqueira Martínez, Gonzalo; Eiroa Pazos, José Manuel; Casteleiro, Manuel (WIT, 2000)[Abstract] The design of safe grounding systems in electrical installations is essential to assure the security of the persons, the protection of the equipment and the continuity of the power supply [1,2]. In order to ... -
On the anomalous asymptotic performance of the regular computer methods for grounding analysis
Colominas, Ignasi; Navarrina, Fermín; Casteleiro, Manuel (2003)[Abstract] Grounding systems are designed to guarantee personal security, protection of equipments and continuity of power supply. Hence, engineers must compute the equivalent resistance of the system and the potential ... -
On the Galerkin formulation of the smoothed particle hydrodynamics method
Cueto-Felgueroso Landeira, Luis; Colominas, Ignasi; Mosqueira Martínez, Gonzalo; Navarrina, Fermín; Casteleiro, Manuel (John Wiley and Sons, 2004)[Abstract] In this paper, we propose a Galerkin-based smoothed particle hydrodynamics (SPH) formulation with moving least-squares meshless approximation, applied to free surface flows. The Galerkin scheme provides a clear ... -
On the intrinsic instability of the advective-diffusive transport
Gómez, Héctor; Colominas, Ignasi; Navarrina, Fermín; Casteleiro, Manuel (2004)[Abstract] A new theory for the advective–diffusive phenomenon is described in this study and the causes for the failure of the conventional numerical methods for this problem are investigated. It is shown that Fick’s law ... -
Optimización de torres de alta tensión mediante un método de programación lineal secuencial con búsqueda unidireccional cuadrática
Navarrina, Fermín; Valera, Augusto; París, José; Colominas, Ignasi; Casteleiro, Manuel (2005)En este trabajo se presenta un sistema de optimización estructural desarrollado específicamente para una determinada familia de problemas. El sistema permite parametrizar automáticamente torres de alta tensión de tipos ...