Numerical modeling of scrap heating by burners

For accurate prediction of flow and temperature field for the scrap heating by burners variable porosity, non-Darcian, turbulent flow with separate temperatures for gas and solids need to be considered. To handle these issues an in-house computer model was developed, considering non-uniform porosity inside the furnace, turbulence, dynamic behavior of porosity due to localized melting. The major challenges during numerical modeling were to use appropriate model parameters such as; porosity variation inside the furnace, permeability of the bed, drag coefficient of the bed, effective thermal conductivity of the bed, fluid to solid heat transfer coefficient and radiation inside the bed. Porosity variation inside the furnace was modeled according to the experimental data. Due to lack of literature of porous media fluid flow and heat transfer for irregular shaped particles and complexity of the problem a detail analysis and considerations of the model parameters were performed. Model parameters were dependent upon porosity of the bed and characteristic particle diameter. Measured porosity variations were used for numerical simulation and characteristic particle diameter for different scrap was tuned to match the experimental results with numerical simulation. Using tuned characteristic particle diameter simulations were performed for different scrap with different furnace configurations.