尾缘锯齿修形对波瓣强迫混合排气系统性能影响

针对某涡扇发动机波瓣强迫混合排气系统建立了尾缘锯齿修形流场数值计算模型,通过三维数值模拟研究,得到了不同尾缘锯齿修形波瓣强迫混合排气系统流场的演变规律和热混合效率、总压恢复系数的变化规律.结果表明:在强迫混合排气系统出口截面处,热混合效率随修形量的增加而增大,总压恢复系数随修形量的增加而减少.1个三角形(1-SJ)锯齿修形模型的热混合效率最大,达到79.73%;2个梯形修形(2-TX)的综合效果最优,其热混合效率达到77.50%,总压恢复系数比1-SJ高出0.5%. 

Effect of serrated cut at trailing edge on performance of lobed mixer in forced mixing exhaust system

Based on a lobed mixer in the forced mixing exhaust system of a turbofan engine,geometric models of different serrated cuts at trailing edge were constructed.Through three-dimensional computational fluid dynamic simulations,the effect of serrated cut at trailing edge on the performance of a lobed mixer in a forced mixing exhaust system on the thermal mixing efficiency and total-pressure recovery coefficient were studied.The results show that the thermal mixing efficiency rises while the total-pressure recovery coefficient declines as the cut size of the serrated cut increases.The thermal mixing efficiency of one triangle (1-SJ) serrated modification model was 79.73%.The thermal mixing efficiency of two trapezoidal modifications (2-TX) was 77.50%,and the total-pressure recovery coefficient of 2-TX was 0.5 percentage higher than that of 1-SJ.