Numerical Simulation of Combustion and Nongray Radiative Heat Transfer in a Furnace and Its Comparison with Experiments

Numerical simulations of heat transfer in a furnace of practical scale were carried out, coupled with a prediction of the flame. Radiative heat transfer was computed taking its nongray characteristic into account. Convective heat transfer to the furnace wall was incorporated as well. The numerical computations were conducted based upon the conservation equations of mass, momentum, energy and species together with the k-ε turbulence model and the eddy dissipation model for estimating the combustion rate and the effective viscosity. Radiative heat transfer was computed using the radiant heat ray method in combination with a weighted-sum-of-gray-gas model or a wide-band model. Predicted results were compared with experimental data. Comparisons showed that the profiles of temperature and species concentration can be predicted fairly well and that the weighted-sum-of-gray-gas model as well as the wide-band model gives a good prediction of heat flux to the furnace wall. The influence of soot on furnace heat transfer was also estimated.