引射/强迫式波瓣混合器开设通气狭缝的流动分离控制
Flow separation control of lobed ejector/forced mixer by ventilation
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摘要: 为了抑制大扩张角波瓣混合器主流侧瓣顶内存在的流动分离现象,在基准波瓣混合器上开设了通气狭缝,通过数值模拟的方法研究了上述处理对次流分别为受迫流动和引射流动两种情况下的波瓣混合器抑制主流流动分离的效果.研究结果表明:①波瓣扩张角小于35°时,波瓣混合器内没有任何的流动分离的现象发生,当波瓣扩张角增大到35°时,波瓣内开始出现流动分离,继续增大波瓣扩张角,则波瓣混合器内流动分离加大;②对于次流为受迫流动的大波瓣扩张角波瓣混合器而言,开设了通气狭缝后,流动分离得到了有效的抑制;③对于次流为引射流动的波瓣混合器而言,对存在流动分离的大波瓣扩张角波瓣混合器开设了通气狭缝后,流动分离并未得到了有效的抑制,通气狭缝的存在提前诱发主流侧流体的分离.Abstract: To control flow separation inside the lobed mixer with a big lobed angle, ventilating treatment was performed on a baseline lobed mixer to reveal the effectiveness of ventilation on eliminating separation bubble inside the lobed mixer when secondary flow is forced or ejected by numerical simulation. Results show that:(1)When the lobed angle is below 35 degrees, no separation is observed; when the lobed angle is at 35 degrees, separation bubble begin to appear inside the lobed nozzle, when the lobed angle is above 35 degrees, separation bubble augments.(2)Ventilating treatment on lobed forced mixer with a big lobed angle is able to eliminate the separation bubble inside the nozzle.(3)The same treatment on the other hand does not banish the separation bubble inside the lobed ejector mixer with a big lobed angle. In fact,the ventilating gap brings forward the separation phenomena rather than avoiding it.
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Key words:
- lobed nozzle /
- lobed angle /
- flow separation /
- ventilation /
- numerical simulation
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[1] Presz W M,Morin B L,Blinn R F.Short efficient ejector systems[R].AIAA-87-1837,1987. [2] 张靖周,单勇,李立国.直升机排气系统用波瓣喷管引射- 混合式红外抑制器研究[J].航空学报,2007,28(1):32-36. ZHANG Jingzhou,SHAN Yong,LI Liguo.Investigation on lobed nozzle mixer-ejector infrared suppressor for helicopter exhaust system[J].Acta Aeronautica et Astronautica Sinica,2007,28(1):32-36.(in Chinese) [3] 单勇,张靖周,李立国.直升机红外抑制器红外辐射特性的数值研究和实验验证[J].红外与毫米波学报,2006,25(4):95-100. SHAN Yong,ZHANG Jingzhou,LI Liguo.Numerical calculation and experimental verification for the inferred radiation characteristics of helicopter infrared radiation suppressor[J].Journal of Infrared and Millimeter Waves,2006,25(4):95-100.(in Chinese) [4] ZHANG Jingzhou,SHAN Yong,LI Liguo.Computation and validation of parameter effects on lobed mixer-ejector performances[J].Chinese Journal of Aeronautics,2005,18(3):193-198. [5] Sokhey J S.Experimental performance evaluation of ventilated mixers:a new mixer concept for high-bypass turbofan engines[J].Journal of Aircraft,1984,21(8):567-575. [6] SHAN Yong,ZHANG Jingzhou,XU Liang.Numerical investigation of aerodynamic and mixing characteristics of scarfed lobed mixer for turbofan engine exhaust system[J].Transactions of Nanjing University of Aeronautics & Astronautics,2009,26(2):130-136. [7] 刘友宏,樊超,谢翌,等.波瓣数对波瓣强迫混合排气系统性能影响[J] 航空动力学报,2010,25(8):1683-2689. LIU Youhong,FAN Chao,XIE Yi,et al.Effect of lobe numbers on the performance of a lobed mixer in the forced mixing exhaust system[J].Journal of Aerospace Power,2010,25(8):1683-2689.(in Chinese) [8] Yu S C M,Hou Y,Chan W K.Scarfing and scalloping effects on lobed forced mixer at low-speed conditions[J].Journal of Propulsion and Power,2000,16(3):440-448. [9] 单勇,张靖周.波瓣喷管结构参数对引射混合器性能影响的数值研究[J].航空动力学报,2005,20(6):973-977. SHAN Yong,ZHANG Jingzhou.Numerical investigation on the effects of lobe nozzle geometric parameters on mixer-ejector performance[J].Journal of Aerospace Power,2005,20(6):973-977.(in Chinese) [10] O'Sullivan M N,Waitz I A,Greitzer E M,et al.A computational study of viscous effects on lobed mixer flow features and performance[R].AIAA-94-3085,1994. [11] 谢杰,许劲松,郁程.圆柱绕流的流动分离控制[J].哈尔滨工程大学学报,2011,34(4):401-406. XIE Jie,XU Jinsong,YU Cheng.A flow separation control on cylinder flow[J].Journal of Harbin Engineering University,2011,34(4):401-406.(in Chinese) [12] 伊进宝,乔渭阳,孙大伟.低压涡轮叶栅流动分离主动控制实验研究[J].航空学报,2007,28(5):1055-1061. YI Jinbao,QIAO Weiyang,SUN Dawei.Experimental investigation of active control of flow separation at low-pressure turbine cascade[J].Acta Aeronautica et Astronautica Sinica,2007,28(5):1055-1061.(in Chinese) [13] 刘小民,周海洋.低压透平叶片流动分离主动控制的数值研究[J].西安交通大学学报,2010,44(9):21-26. LIU Xiaomin,ZHOU Haiyang.Numerical study on active flow separation control for low-pressure turbine blade[J].Journal of Xi'an Jiaotong University,2010,44(9):21-26. [14] 周杨,邹正平,刘火星,等.边界层吹吸气对高负荷扩压叶栅性能的影响[J].推进技术,2007,28(6):647-652. ZHOU Yang,ZOU Zhengping,LIU Huoxing,et al.Effects of co-flow jets in boundary layer on highly loaded compressor cascade performance[J].Journal of Propulsion Technology,2007,28(6):647-652.(in Chinese) [15] 李应红,梁华,马清源,等.脉冲等离子体气动激励抑制翼型吸力面流动分离的实验[J].航空学报.2008,29(6):1429-1435. LI Yinghong,LIANG Hua,MA Qingyuan,et al.Experimental investigation on airfoil suction side flow separation by pulse plasma aerodynamic actuation[J].Acta Aeronautica et Astronautica Sinica,2008,29(6):1429-1435.(in Chinese) [16] 吴云,李应红,朱俊强,等.等离子体气动激励抑制压气机叶栅角区流动分离的仿真与实验[J].航空动力学报,2009,24(4):830-835. WU Yun,LI Yinghong,ZHU Junqiang,et al.Computational and experimental investigation of plasma aerodynamic actuation based corner flow separation control in a compressor cascade[J].Journal of Aerospace Power,2009,24(4):830-835.(in Chinese)
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