A computational study of turbulent evaporating and combustion sprays is reported. The major focus is to develop a solution procedure and to examine the detailed effects of fuel atomisers with and without swirl on droplet behavior and spray characteristics in reacting and non-reacting flows. A hybrid Eulerian-Lagrangian method is employed to model the reactive and isothermal flow-field of the combustor. The equations governing the gas are solved by a control-volume based semi-implicit iterative procedure and the sets of time-dependent differential equations for each of the drop sizes are integrated by a semi-analytic method. The calculation procedure is applied to the case of spray combustion in an axisymmetric combustor and the results are compared with experimental data. Computational results show the detailed effects of fuel atomiser design parameters (such as nozzle angle and swirl) on evaporation rate and combustor performance. The calculations show that the droplet trajectory and vaporization characteristics are strongly influenced by the atomization technique.The results also indicate that swirl atomizers have the ability to burn “difficult” fuels (e.g. fuels with low calorific value or high boiling point).

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