Ponències/Comunicacions de congressoshttp://hdl.handle.net/2117/797082018-11-17T03:33:05Z2018-11-17T03:33:05ZMulti-objective design optimisation of stamping process for advanced high strength steelsLee, Dong SeopPons Prats, JordiEspinoza Román, Héctor GabrielFruitós Bickham, Óscar AlejandroOñate Ibáñez de Navarra, Eugeniohttp://hdl.handle.net/2117/1178302018-06-06T01:39:59Z2018-06-05T12:33:55ZMulti-objective design optimisation of stamping process for advanced high strength steels
Lee, Dong Seop; Pons Prats, Jordi; Espinoza Román, Héctor Gabriel; Fruitós Bickham, Óscar Alejandro; Oñate Ibáñez de Navarra, Eugenio
The paper investigates the multi-objective design optimisation of stamping process to control both the shape and quality of final Advanced High Strength Steels (AHSSs) in terms of springback and safety using Distributed Multi-Objective Evolutionary Algorithm (DMOGA) coupled with Finite Element Analysis (FEA) based stamping analyser. The design problem of stamping process is formulated to minimise the difference between the desired shape and the final geometry obtained by a numerical simulation accounting elastic springback.
2018-06-05T12:33:55ZLee, Dong SeopPons Prats, JordiEspinoza Román, Héctor GabrielFruitós Bickham, Óscar AlejandroOñate Ibáñez de Navarra, EugenioThe paper investigates the multi-objective design optimisation of stamping process to control both the shape and quality of final Advanced High Strength Steels (AHSSs) in terms of springback and safety using Distributed Multi-Objective Evolutionary Algorithm (DMOGA) coupled with Finite Element Analysis (FEA) based stamping analyser. The design problem of stamping process is formulated to minimise the difference between the desired shape and the final geometry obtained by a numerical simulation accounting elastic springback.Stabilized finite element formulation for the mixed convected wave equation in domains with driven flexible boundariesGuasch Fortuny, OriolArnela, MarcCodina, RamonEspinoza Román, Héctor Gabrielhttp://hdl.handle.net/2117/766082015-11-17T12:56:25Z2015-09-03T16:35:10ZStabilized finite element formulation for the mixed convected wave equation in domains with driven flexible boundaries
Guasch Fortuny, Oriol; Arnela, Marc; Codina, Ramon; Espinoza Román, Héctor Gabriel
A stabilized finite element (FEM) formulation for the wave equation in mixed form with convection is presented, which permits using the same interpolation fields for the acoustic pressure and the acoustic particle velocity. The formulation is based on a variational multiscale approach, in which the problem unknowns are split into a large scale component that can be captured by the computational mesh, and a small, subgrid scale component, whose influence into the large scales
has to be modelled. A suitable option is that of taking the subgrid scales, or subscales, as being related to the finite element residual by means of a matrix of stabilization parameters. The design of the later turns to be the key for the good performance of the method. In addition, the mixed convected wave equation has been set in an arbitrary Lagrangian-Eulerian (ALE) frame of reference to account for domains with moving boundaries. The movement of the boundaries in the present work consists of two components, an external prescribed motion and a motion related to the boundary elastic back reaction to the acoustic pressure, in the normal direction. A mass-damper-stiffness auxiliary equation is solved for each boundary node to include this effect. As a first benchmark example, we have considered the case of 2D simple duct acoustics with mean flow. More complex 3D examples are also presented consisting of vowel and diphthong generation, following a numerical approach to voice production. The numerical simulation of voice not only allows one to see how waves propagate inside the vocal tract, but also to collect the
acoustic pressure at a node close to the mouth exit, convert it to an audio file and listen to it.
2015-09-03T16:35:10ZGuasch Fortuny, OriolArnela, MarcCodina, RamonEspinoza Román, Héctor GabrielA stabilized finite element (FEM) formulation for the wave equation in mixed form with convection is presented, which permits using the same interpolation fields for the acoustic pressure and the acoustic particle velocity. The formulation is based on a variational multiscale approach, in which the problem unknowns are split into a large scale component that can be captured by the computational mesh, and a small, subgrid scale component, whose influence into the large scales
has to be modelled. A suitable option is that of taking the subgrid scales, or subscales, as being related to the finite element residual by means of a matrix of stabilization parameters. The design of the later turns to be the key for the good performance of the method. In addition, the mixed convected wave equation has been set in an arbitrary Lagrangian-Eulerian (ALE) frame of reference to account for domains with moving boundaries. The movement of the boundaries in the present work consists of two components, an external prescribed motion and a motion related to the boundary elastic back reaction to the acoustic pressure, in the normal direction. A mass-damper-stiffness auxiliary equation is solved for each boundary node to include this effect. As a first benchmark example, we have considered the case of 2D simple duct acoustics with mean flow. More complex 3D examples are also presented consisting of vowel and diphthong generation, following a numerical approach to voice production. The numerical simulation of voice not only allows one to see how waves propagate inside the vocal tract, but also to collect the
acoustic pressure at a node close to the mouth exit, convert it to an audio file and listen to it.