In single can combustor ignition tests, different results were obtained for pressure atomizing and airblast atomizing fuel injectors as well as for various ignition locations. In order to understand the effect of fuel spray characteristics and ignition locations on gas turbine combustion ignition characteristics, a computer simulation of fuel droplet ignition at engine starting flow conditions has been conducted. An ignition model for evaporating fuel droplets was incorporated with the numerical droplet tracking scheme in the computational flow field, which included a simulated ignition point source. A large number of various size droplets were computed for their trajectories and ignition reactions. A statistical data base was established to calculate the ignition probability of droplets in terms of number and mass fraction. A correlation between predicted ignition probability trends and experimental ignition data for two different injector/ignitor configurations was demonstrated.
Numerical Correlation of Gas Turbine Combustor Ignition
