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Show 1. Introduction The modelling the flow and heat transfer in a gas-fired furnace and its comparison to experimental data has been reported by various authors [1-9]. Most of these works were conducted on a small-scale tunnel furnace which employed a single burner. The tunnel furnace does not, however, display important features of the aerodynamics and heat transfer found in industrial furnaces of complex design. The present work was carried out on a gas fired research furnace fitted with three industrial burners. The furnace, Fig. 1, presents in adequate degree, qualitatively and quantitatively within the practical operating domain, the essential features of the target class of real furnaces. Therefore, the validation of the mathematical furnace model can be validated against complex pattern of flow and heat transfer. research furnace. The present contribution extends the work of Rubini et al. [10] in which the three dimensional modelling of cold flow was tested and found to be in good agreement experimental data. In the mathematical modelling of flow and heat transfer in large furnaces with many burners and complex furnace geometry, the treatment of burners and flames must be kept as simple as possible, because of the enormous computational demands of the problem as a whole. Typically the active combustion zones occupy only a small fraction of the furnace volume, so great veracity in burner and flame modelling is unnecessary. However, the requirements of the conservation of mass, momentum and energy must be satisfied. In this work, a burner is a burner is represented by a small array of square surfaces over which the velocities are determined to match mass and mOIl)entum of the experimental burners. The CAGCT research furnace is equipped with diagnostic instrumentation which provides means to measure the heat transfer to the cooled floor, local hemispherical irradiance, mean velocity components with a 5-hole probe, gas temperature with a microthermocouple, local furnace wall temperatures, and gas composition. For this report, only the sink heat fluxes and the refractory wall temperatures are considered. In the following, we briefly describe the governing equations, experiments, computational procedure, and results. The representation of burner exit conditions and the treatment of combustion model are elaborated in more detail in a separate section to provide a clear explanation of this approach. 2 |