Effects of Penetration Angle and Width Ratio of Lobed Mixer on Mixing and Combustion Performance in ATR Combustors

The lobed mixers were designed based on the ATR combustor inlet structure to facilitate the mixing and combustion of the air from the compressor and the fuel-rich gas from the turbine, and the numerical methods were used. The structure of lobe was optimized by increasing the penetration angle and the lobe width ratio. The relevant results show that: (1) Keeping the inner penetration angle constant and increasing the inner penetration angle, the status of incomplete combustion in the center area of the combustor can be alleviated effectively. (2) Keeping the inner and outer penetration angles constant and decreasing the lobe width b2 at the trailing edge so that the lobe width ratio B is less than 1 can increase the mixing and combustion efficiencies. (3) Compared with the non-reacting flow, the streamwise vortex induced by the lobed mixer has higher intensity and radial velocity in the reacting flow. (4) In combustors with the lobed mixers, the total pressure loss caused by the mixing between the core and bypass flows is small, more than 80% of total pressure loss is caused by the heating process. © 2021, Editorial Department of Journal of Propulsion Technology. All right reserved.