关键词: 航空发动机;燃烧室;分配器式扩压器;总压损失;数值模拟

Abstract: To decrease the total pressure loss of diffuser of aircraft engine combustor and increase its static pressure recovery as well as flow stability, a distributor type diffuser was designed. Numerical simulation of rectangular and annular distributor type diffusers were conducted at different Mach numbers by means of computational fluid dynamics (CFD). The simulation results of rectangular distributor type diffuser are in good agreement with the experimental data, showing a deviation of less than ±5%. Results show that CFD software can accurately simulate the inner flow of rectangular distributor type diffuser.The calculation approach was used to study the performance of annular distributor type diffuser. The accuracy is high enough that the difference between simulation results and experimental results is less than±5%. Annular distributor type diffuser has excellent diffusion performance. When combustor inlet Mach number is 0.36, the total pressure loss coefficient and static pressure recovery coefficient of the designed annular distributor type diffuser are 2.89% and 0.647,respectively.When Mach number is 0.42, the total pressure loss coefficient and static pressure recovery coefficient are 4.12% and 0.653, respectively. These figures are less than those of dump diffuser. In addition, the flow separation was not found in the diffuser. Hence, an annular distributor type diffuser potentially satisfies the requirements of high performance combustors. 

Key words: Aircraft engine；Combustor；Distributor type diffuser；Total pressure loss；Numerical simulation