Simulation of fuel film formation in ducts

The fuel/air mixing processes in spark ignition engines are currently receiving considerable attention due to the combined requirements of minimising both global and local pollution levels while maintaining high engine efficiencies. During preparation for combustion in the intake manifold, the fuel flow exists in several streams, these being vapour, liquid droplets and liquid wall film. While this research is aimed at examining fuel film behaviour in general, the particular emphasis of this paper is on the application of a numerical technique to obtain a better understanding of film formation. A number of specific configurations have been examined and can be compared with experimental data from a specially designed rig. While precise experimental measurements are not yet available, the numerical results correspond well with the qualitative assessment from the rig.