NUMERICAL SOLUTION OF A TIME-DEPENDENT SIGNORINI CONTACT PROBLEM

International audienceThe purpose of this work is to study the dynamic frictionless contact problem between an elastic body and a rigid foundation. In order to model the contact we consider Signorini conditions. A numerical algorithm is proposed to approximate the solution; the algorithm involves a contact multi-plier, which is a fixed point of a nonlinear equation solved by using a generalized Newton method. We use one of the Newmark methods for time discretization and a finite element method for space discretization. The convergence of the method is numerically studied, and a simple test problem is used to validate the methodology

Numerical simulation of the shear stress produced by the hot metal jet on the blast furnace runner

During steel casting process a jet of molten metal runs out of the blast furnace hearth and strikes the runner. The continuous impact of hot fluids causes significant damage to its surface, which is made of refractory concrete. In particular, the initial impact on the dry runner is expected to be critical. This work deals with the analysis of the mechanical impact on the runner through the numerical simulation of the process. We propose an incompressible turbulent isothermal Navier-Stokes model, where turbulence is modelled considering two models (standard and SST). The interface dynamics is described by applying the Volume of Fluid (VOF) method, while the surface tension vector is provided by the Continuum Surface model (CSF). Their numerical results are performed in 2D. A comparative analysis of the most suitable transient turbulent multiphase model is presented by simulating benchmark physical experiments. The shear stress arising from the impact of the jet on the runner is also analyzed. An improvement of the classical analytical expression given in [1] is proposed. Both, the chosen turbulence model, and the formulas to compute the shear stress are validated using two benchmark laboratory tests and three numerical experiments. Numerical results are given for the impact of the jet on the dry runner of the blast furnaceThis work was supported by FEDER and Xunta de Galicia [grant number ED431C 2017/60, ED431C 2021/15], the Ministry of Economy, Industry and Competitiveness through the Plan Nacional de I+D+i [grant number MTM2015-68275-R], Agencia Estatal de Investigación [PID2019-105615RB-I00/AEI/10.13039/501100011033] and by the Vicerreitoría de Investigación e Innovación da Universidade de Santiago de Compostela via the Programa de Becas de Colaboración en Investigación 2016S

Transient thermal response with nonlocal radiation of a blast furnace main trough

A mathematical model for the transient thermal behaviour of the main trough of a blast furnace (BF) is presented. The proposed model consists of the transient heat equation with mixed radiation-convection boundary conditions to model the cooling process. The heat equation is coupled with an integral equation posed on the inner boundary, which models the radiative heat exchange on the internal cavity formed by the trough and the refractory cover placed over the trough. The main scope of this work is to address the evolution of the temperature field during a full BF tapping. A reliable algorithm, capable of simulating entire trough campaigns, is presented. The open-source computing platform FEniCS is used to numerically solve the model using a finite element method. A manufactured solution test for the heat diffusion coupled with 2D nonlocal radiation is defined with the purpose of verifying the implementation, comparing the performance of different time discretization schemes and the adaptive time stepping algorithm. Concerning the BF tapping problem, the results show that during the time interval corresponding to a single tapping, the temperature in the radiation enclosure swiftly reaches the steady state value. Nevertheless, to obtain a steady state in the bulk of the solids, much longer time scales are needed due to the large thermal inertia of the structureThis work was partially supported by ERDF and Xunta de Galicia funds under the ED431C 2017/60 and the ED431C 2021/15 grants, by the Ministerio de Ciencia, Innovación y Universidades through the Plan Nacional de I+D+i (MTM2015-68275-R) and the grant BES-2016-077228, and by the Agencia Estatal de Investigación through project [PID2019-105615RB-I00 / AEI / 10.13039/501100011033]S

Novel methodologies for solving the inverse unsteady heat transfer problem of estimating the boundary heat flux in continuous casting molds

In this article, we investigate the estimation of the transient mold-slab heat flux in continuous casting molds given some thermocouples measurements in the mold plates. Mathematically, we can see this problem as the estimation of a Neumann boundary condition given pointwise state observations in the interior of the domain. We formulate it in a deterministic inverse problem setting. After introducing the industrial problem, we present the mold thermal model and related assumptions. Then, we formulate the boundary heat flux estimation problem in a deterministic inverse problem setting using a sequential approach according to the sequentiality of the temperature measurements. We consider different formulations of the inverse problem. For each one, we develop novel direct methodologies exploiting a space parameterization of the heat flux and the linearity of the mold model. We construct these methods to be divided into a computationally expensive offline phase that can be computed before the process starts, and a cheaper online phase to be performed during the casting process. To conclude, we test the performance of the proposed methods in two benchmark casesAgencia Estatal de Investigación, Grant/Award Number: PID2019-105615RBI00/AEI; European Research Council, Grant/Award Number:765374; H2020 Marie Skłodowska-Curie Actions, Grant/Award Number: 681447; Ministerio de Economía, Industria y Competitividad, Gobierno de España, Grant/Award Number: MTM2015-68275-RS

I-MATH map of company demand for mathematical technology: TransMATH

This document details a Spanish prospectus on the level of knowledge, use and demand for mathematical technology by commercial companies. It is aimed at detecting problems in the corporate field for which Mathematicians could provide the complementary or fundamental tools, determine the demand for mathematical training, and define where necessary new lines of research in Mathematics aimed at solving these problem

RSME 2011. Transfer and Industrial Mathematics. Proceedings of the RSME Conference on Transfer and Industrial Mathematics. Santiago de Compostela, July 12-14, 2011

[EN] The RSME Conference on Transfer and Industrial Mathematics is supported by the Royal Spanish Mathematical Society, a scientific society for the promotion of mathematics and its applications as well as the encouragement of research and teaching at all educational levels. The three-day conference presents successful experiences in the field of mathematical knowledge transfer to industry and focuses on the following issues: — Showing how collaboration with industry has opened up new lines of research in the field of mathematics providing high quality contributions to international journals and encouraging the development of doctoral theses. — How the promotion of existing infrastructures has contributed to enhance the transfer of mathematical knowledge to industry. — The presentation of postgraduate programs offering training in mathematics with industrial applications. The conference includes talks from researchers and industry representatives who present their different points of view and experiences with regards to the transfer of mathematical knowledge to industry

Mapa i-MATH de demanda empresarial de tecnología matemática: Transmath

Este documento recoge una prospectiva nacional sobre el grado de conocimiento, de utilización y de demanda de tecnología matemática en la empresa. El documento trata de detectar problemas empresariales en los que las Matemáticas puedan ser una herramienta complementaria o fundamental, conocer la demanda de formación matemática y definir, si es necesario, nuevas líneas de investigación en Matemáticas orientadas a resolver estos problema

Reports about 8 selected benchmark cases of model hierarchies : Deliverable number: D5.1 - Version 0.1

Based on the multitude of industrial applications, benchmarks for model hierarchies will be created that will form a basis for the interdisciplinary research and for the training programme. These will be equipped with publically available data and will be used for training in modelling, model testing, reduced order modelling, error estimation, efficiency optimization in algorithmic approaches, and testing of the generated MSO/MOR software. The present document includes the description about the selection of (at least) eight benchmark cases of model hierarchies.EC/H2020/765374/EU/Reduced Order Modelling, Simulation and Optimization of Coupled Systems/ROMSO

Elasticidad no lineal. Modelo de Von Karman

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid. Facultad de Ciencias. Departemento de Matemáticas. Fecha de lectura: 26-06-198