Experiment on lean blow-out performance of pilot stage in internally-staged combustor

An experimental research was conducted on the lean LBO (blow-out) performance at constant pressure status of internally-staged single annular layout LESS (low emissions stirred swirl) combustor. Using single head speeimen, this experiment mainly focused on the effect of three parameters on the combustor lean blow-out performance, i. e. mass flow number of the pilot stage centrifugal nozzle, inlet temperature and the fuel type, respectively. The experimental result shows that: the pilot stage centrifugal nozzle with small mass flow number can reduce LBO equivalence ratio. When the inlet temperature is below 150℃, increasing the inlet temperature can reduce LBO equivalence ratio rapidly; but there is little effect when the inlet temperature exceeds 150℃. LBO equivalence ratio variational trends of gaseous fuel is different from those of liquid fuel with the flame tube pressure drop, but they tend to be the same value, and when the flame tube pressure drop is in the range of 5%, LBO equivalence ratio of gaseous fuel is less than that of liquid fuel.