V形尾缘分开排气喷管喷流流场的数值模拟  

Numerical simulation on jet flow field of separate flow nozzles with chevron trailing edge

作　　者：康冠群[1] 王强[1] 

机构地区：[1]北京航空航天大学能源与动力工程学院,北京100191

出　　处：《航空动力学报》2011年第1期154-160,共7页Journal of Aerospace Power

摘　　要：采用二阶迎风离散格式并选用RNG(renormalization group)k-ε湍流模型,对轴对称分开排气喷管和核心喷管上采用V形尾缘的分开排气喷管的喷流流场进行三维数值模拟.结果表明,相对基准轴对称分开排气喷管,V形尾缘一方面引入了流向涡,另一方面增加了核心喷流与风扇喷流之间的混合层长度,强化了喷流的混合,有效地缩短了热核心区的长度,降低了喷流中心线附近的最大速度.此外,V形尾缘随着偏转角度的增加在一定的轴向范围内显著地减小了喷流速度和总温,相对而言,V形尾缘长度的增加对喷流混合的加强作用并不明显.Three-dimensional numerical simulations for the jet flow field of separate flow nozzles with/without chevrons on core nozzle were carried out. Calculation was conducted by employing second order upwind discretization scheme and RNG （renormatization group） k-e turbulent model. As compared with baseline axisymmetric separate flow nozzle, addition of chevrons can strengthen the jet mixing since chevrons introduce streamwise vortices and increase the length of the mixing layer between core stream and fan stream, resulting in ob- vious reduction of hot potential core length and the decay of jet maximum velocity near the centerline. Moreover, increment of chevron deflection angle greatly enhances vortex strength so as to decrease jet velocity and total temperature substantially in a certain axial range. Relatively, reinforcement of jet mixing with increment of chevron length is not evident.

关 键 词：分开排气 V形尾缘 喷流流场 数值模拟 强化混合 

分 类 号：V231.3[航空宇航科学与技术—航空宇航推进理论与工程]