Study on the Influence of Fuel Supply and Distribution on the Performance of Concentric Staged High Temperature Rise Combustor

Based on the increasing demand for high thrust-to-weight ratio and high temperature rise of military aero-engines, a design scheme of combustor with concentric staged combustion organization is proposed. The main combustion stage of the swirler is a combination of swirling and non-swirling air intake. The verified one-dimensional calculation method is used to calculate and evaluate the performance of the combustion chamber. Based on the verification of three-dimensional numerical method and grid independence, the effects of fuel supply and distribution on combustor performance are studied. The studies show that the combustion efficiency and outlet temperature distribution could be improved when the axial position of the pilot nozzle is located at the outlet of vane channel. However, it will cause the problem that the high temperature flame is too close to the outlet of swirler. With the increase of the main nozzle angle, the combustion efficiency increases, and the overall temperature distribution factor (OTDF) decreases gradually. The fuel distribution ratio of main stage has a great impact on the field of temperature. The increase of fuel distribution ratio is contributed to improve the combustion efficiency and reduce the OTDF, while the total pressure loss coefficient increases slightly within a certain range. However, when the fuel distribution ratio exceeds 80%, the temperature near the baffle plate of dome is overheated, and the improvement effect of combustion efficiency is no longer obvious.