Analysis on swirl cup combustor near lean blow out point with flamelet model

The experimental data on lean blow out fuel/air ratio of a single-dome swirl cup combustor was obtained at 388 K inlet temperatures and atmospheric pressure with different inlet air velocities.Using flamelet combustion model with detailed chemical mechanism,numerical simulations were performed to get the details of local hot flow field.Results show that,near the lean blow out point,with the decline of fuel/air ratio,the vortex core is separated from high temperature zone,and the temperature in recirculation zone drops,and the ignition point moves backward,so the ignition distance increases.With the increase of inlet air velocity and decrease of the fuel mass flow rate,the mass flow rate of the recirculation and the temperature difference between two sides of the vortex core become greater,but the ignition point stays further back,showing that the flame has greater tolerance with their difference.