MODELO MATEMÁTICO DAS FORÇAS DE NÃO-ARRASTE NO ESCOAMENTO BIFÁSICO DO DESGASEIFICADOR RH
MATHEMATICAL MODEL OF THE NON-DRAG FORCES IN TWO-PHASES FLOW OF RH DEGASSER
Neves, Leonardo; Tavares, Roberto Parreiras
Resumo
No presente trabalho foi feito um estudo do escoamento bifásico do desgaseificador RH em modelos físicos. A modelagem matemática do foi feita utilizando a abordagem de dois fluidos Euleriana-Euleriana. Foi feito um estudo da influência das diferentes forças de não-arraste, tais como: força de dispersão turbulenta, força de lubrificação da parede e força de sustentação. No estudo foi empregado o modelamento matemático na determinação da taxa de circulação no modelo físico do desgaseificador RH da USIMINAS na escala de 1:5. Para a validação dos resultados do modelamento matemático, ensaios foram feitos utilizando estes modelos físicos empregando técnicas para obtenção de tempo de homogeneização de soluções salinas. O acompanhamento do escoamento foi feito através de filmagens utilizando câmera comum e câmera de alta velocidade. Foi determinado que as forças de não-arraste influenciam no escoamento bifásico ar/água sendo a combinação das forças de dispersão turbulenta, lubrificação das paredes e sustentação que possuíram os melhores resultados, ao serem comparados com os resultados experimentais.
Palavras-chave
Abstract
In the present work a biphasic flow study of the RH degasser was carried out in physical models. The mathematical modeling was made using the Eulerian approach. The influence of different non-drag forces was studied, such as: turbulent dispersion force, wall lubrication force and lift force. In the study, the mathematical modeling was used to determine the circulation rate in the physical model of the RH degasser of USIMINAS in the 1:5 scale. For the validation of the mathematical model, tests were made in the physical model using techniques to obtain homogenization time of salt solutions. The flow monitoring was done by using ordinary camera and high-speed camera. It was determined that the non-drag forces have influence on the two-phase flow (air/water) and the combined forces of turbulent dispersion, wall lubrication force and lift force lead to best results, when compared with the experimental results. Non-drag forces were determined to influence the air / water two-phase flow, the combination of turbulent dispersion, wall lubrication and lifting forces having the best results compared to the experimental results
Keywords
Referências
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