THE EFFECT OF KEY ASPECTS ON THE THERMOMECHANICAL BEHAVIOUR OF TORPEDO LADLE BRICKS USING FINITE ELEMENT ANALYSIS
O EFEITO DE ASPECTOS CHAVE NO COMPORTAMENTO TERMOMECANICO DE TIJOLOS PARA CARRO TORPEDO UTILIZANDO ANÁLISE POR ELEMENTOS FINITOS
Ana Paula de Miranda Mati, Rubens Alves Freire, Sergio Luiz Cabral da Silva, Paulo Roberto Brandão
Abstract
In the current paper, the effect of some aspects, e.g., thermal expansion, thermal conductivity and hot mechanical behavior, on the thermomechanical behavior of Al2O3-SiC-C brick, typically used in torpedo ladles, is described. Computational modeling by finite element analysis (FEA) was applied in an attempt to better understanding the relative importance of each variable for the development of refractories with enhanced spalling resistance. The simulations by FEA indicated that the failure criteria selected in this work are in accordance with the spalling mechanism proposed in the literature and with practical observations. As the stress values were systematically higher after the breakage of the bricks’ edges, it seems more reasonable to avoid spalling by hindering the formation of broken edges than by avoiding the phenomenon itself. The effect of key aspects on the thermomechanical behavior of Al2O3-SiC-C brick was simulated. The key variables to be controlled are the following: stress, thermal expansion, strain and thermal conductivity
Keywords
Resumo
No presente trabalho, descreve-se o efeito de alguns aspectos, tais como, expansão térmica, condutividade térmica e comportamento mecânico quente, no comportamento termomecânico do tijolo Al2 O3 -SiC-C, tipicamente usado em panelas de torpedo. Modelagem computacional por análise de elementos finitos (FEA) foi aplicada na tentativa de melhor compreender a importância relativa de cada variável para o desenvolvimento de refratários com maior resistência ao lascamento. As simulações da FEA indicaram que os critérios de falha selecionados neste trabalho estão de acordo com o mecanismo proposto na literatura e com as observações práticas. Como os valores de tensão foram sistematicamente mais altos após a quebra das bordas dos tijolos, parece mais razoável evitar a fragmentação impedindo a formação de bordas quebradas do que evitando o fenômeno em si. O efeito de aspectos-chave no comportamento termomecânico do tijolo Al2 O3 -SiC-C foi simulado. As principais variáveis a serem controladas são as seguintes: tensão, expansão térmica, deformação e condutividade térmica.
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Referências
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