An optimization analysis of inlet mass flow splits of ultracompact interturbine burner was introduced. The combustion performance in a smallscale interturbine burner was numerically analyzed using Chemkin software

and a detail kerosene RP3/air mechanism was used. Numerical results were qualitatively validated with the existing experimental data with respect to the combustion performance. Five split ratios of the core mass flow rate to cavity mass flow rate

60/40

65/35

70/30

75/25 and 80/20

were adopted to contrastively study the outlet temperature

combustion efficiency and pollutant emission using the simplified model. The results show that the combustion efficiency of the split ratio 65/35 decreasesd by 0249% compared with the highest efficiency among the five split ratios

but the NOx and CO emissions both decrease more than 50%. The conclusion based on this method can provide a basis for evaluating an optimum mass flow split at the design stage of ultracompact interturbine burner as well as for simplified performance analysis.