Modelagem numérica da transferência de calor do processo de lingotamento contínuo de tarugo oco de cobre em uma planta industrial
Numerical modeling of the continuous casting hollow billets heat transfer in industrial plant
Edson Fouad Beck Filho, Paulo Jesus Aniceto, Noé Cheung, Carlos Henrique da Silva Santos, Felipe Bertelli
Resumo
O objetivo do trabalho é apresentar uma metodologia numérica envolvendo o modelamento matemático da transferência de calor radial, baseado no Método das Diferenças Finitas, para simular a solidificação de tarugos cilíndricos ocos de cobre puro durante a passagem pelo molde primário de refrigeração. Foi utilizado o método do problema inverso em condução de calor aplicado à solidificação para determinação do coeficiente global de transferência de calor na interface metal/molde (hg ) considerando cinco temperaturas experimentais em posições distintas da superfície do lingote, para uma corrida com velocidade de 180mm/min. Posteriormente, foram estimadas, via simulação numérica, as distribuições internas de temperatura e gerados os perfis térmicos bidimensionais no sentido longitudinal de lingotamento, bem como da secção transversal ao sentido de lingotamento. Os resultados evidenciaram uma heterogeneidade na troca térmica entre o lingote e o molde de refrigeração, considerando diferentes posições angulares em relação a secção transversal de lingotamento, indicando a maior eficiência na transferência de calor na região inferior do molde e o oposto na região superior.
Palavras-chave
Abstract
The objective of the work is to present a numerical methodology involving the mathematical modeling of the radial heat transfer, based on the Finite Differences Method, to simulate the solidification of pure copper hollow billets during their passage through the primary cooling region at the mold of a continuous casting equipment. The inverse problem method in heat conduction applied to solidification was used to determine the global heat transfer coefficient at the metal/mold interface (hg ) basing on five experimental surface temperatures at different positions, considering a casting speed of 180 mm/min. Subsequently, inner temperature distributions were estimated using numerical simulation and the two-dimensional thermal profiles were generated for the longitudinal casting direction, as well as for the cross section to casting direction. The results showed a heterogeneity in the thermal exchange between the ingot and the cooling mold, considering different angular positions in relation to the cross section of the casting, indicating greater efficiency in the lower region of the mold and the opposite side at the upper region.
Keywords
Referências
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Submetido em:
25/06/2020
Aceito em:
05/01/2021
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