Effect of attack angle on stability and transition in a swept-wing boundary layer
-
摘要: 攻角是影响后掠机翼边界层横流稳定性的关键参数之一.以NACA0012翼型为研究对象,通过求解三维可压缩Navier-Stokes方程计算了展向无限长后掠机翼的基本流场;通过求解Orr-Sommerfeld方程得到了扰动波的中性曲线及增长率演化曲线,基于线性稳定性理论(LST)研究了攻角对后掠机翼边界层流动稳定性的影响;最后采用转捩预测eN方法进行了转捩预测.研究发现,扰动波的增长在背风面受到抑制,在迎风面受到增强;转捩首先发生在迎风面,当扰动速度为来流速度的0.05%时,转捩发生的N值在6左右,转捩发生的位置在0.1~0.2个弦长之间.Abstract: Attack angle is one of the key parameters to the cross-flow instability of swept-wing boundary layers. For swept NACA0012 airfoil with infinite spanwise length, the basic flow field was calculated by solving the three-dimensional compressible Navier-Stokes equations numerically, the neutral curve and the evolution curve of growth rate were obtained by solving the Orr-Sommerfeld equation, the effect of attack angle on the cross-flow stability was analyzed by linear stability theory (LST), and the transition position was predicted by eN method. It is found that, the growth of unstable waves in the leeward is inhibited but enhanced in the windward. Transition firstly occurs in the windward, and the transition position predicted by eN method is about 0.1 to 0.2 of the chord length with the N factor of about 6 when the disturbance velocity is 0.05% of the free-stream velocity.
-
Key words:
- attack angle /
- swept-wing /
- hydrodynamic stability /
- transition /
- eN method
-
[1] Joslin R D.Overview of laminar flow control[M].Virginia:National Aeronautics and Space Administration, Langley Research Center, 1998. [2] 周恒,赵耕夫.流动稳定性[M].北京:国防工业出版社, 2004:157-158. Zhou H, Zhao G F.Hydrodynamic stability[M].Beijing:National Defense Industry Press, 2004:157-158(in Chinese). [3] 吴永健.横流不稳定性实验研究[D].南京:南京航空航天大学, 2002. Wu Y J.Experimental study on crossflow instabilities in the boundary-layer of swept wing[D].Nanjing:Nanjing University of Aeronautics and Astronautics, 2002(in Chinese). [4] Boltz F W, Kenyon G C, Allen C Q.Effects of sweep angle on the boundary-layer stability characteristics of an untapered wing at low speeds, Technical Note:D-338[R].Moffett Field:National Aeronautics and Space Administration, 1960. [5] Haynes T S.Nonlinear stability and saturation of crossflow vortices in swept-wing boundary layers[D].Tempe:Arizona State University, 1996. [6] Dagenhart J R, Saric W S.Crossflow stability and transition experiments in swept-wing flow[M].Virginia:National Aeronautics and Space Administration, Langley Research Center, 1999:1, 7. [7] Reibert M S, Saric W S.Review of swept-wing transition, AIAA-1997-1816[R].Reston:AIAA, 1997. [8] Bushnell D M, Malik M R, Harvey W D.Transition prediction in external flows via linear stability theory[C]//Symposium Transsonicum Ⅲ.Berlin Heidelberg:Springer-Verlag, 1988:225. [9] Arnal D, Gasparian G, Salinas H.Recent advances in theoretical methods for laminar-turbulent transition prediction[J].AIAA, 1998:98-0223. [10] 孙朋朋,黄章峰.后掠角对后掠机翼边界层稳定性及转捩的影响[J].北京航空航天大学学报, 2015, 41(7):1313-1321. Sun P P, Huang Z F.Effect of the sweep angle on the stability and transition in a swept-wing boundary layer[J].Journal of Beijing University of Aeronautics and Astronautics, 2015, 41(7):1313-1321(in Chinese). [11] 李锋,汪翼云,崔尔杰.翼型大攻角绕流的数值模拟[J].航空学报, 1992, 13(1):17-22. Li F, Wang Y Y, Cui E J.The numerical simulation of compressible flow around an airfoil at high angle of attack[J].Acta Aeronautica et Astronautica Sinica, 1992, 13(1):17-22(in Chinese). [12] 吴鋆,王晋军,李天.NACA0012翼型低雷诺数绕流的实验研究[J].实验流体力学, 2013, 27(6):32-38. Wu J, Wang J J, Li T.Experimental investigation on low Reynolds number behavior of NACA0012 airfoil[J].Journal of Experiments in Fluid Mechanics, 2013, 27(6):32-38(in Chinese). [13] 吴鋆,李天,王晋军.低Reynolds数NACA0012翼型绕流的流动特性分析[J].实验力学, 2014, 29(3):265-272. Wu J, Li T, Wang J J.Characteristic analysis of flow around NACA0012 airfoil in a low-Reynold-number media[J].Journal of Experimental Mechanics, 2014, 29(3):265-272(in Chinese). [14] 袁湘江,李国良,刘智勇,等.小攻角高超声速钝锥边界层失稳特性[J].航空动力学报, 2011, 26(12):2805-2811. Yuan X J, Li G L, Liu Z Y, et al.Study of the instability characteristic in the boundary layer of a hypersonic blunt cone at low angle of attack[J].Journal of Aerospace Power, 2011, 26(12):2805-2811(in Chinese). [15] 王斌,白存儒,杨广郡,等.后掠机翼低速流动转捩位置的升华法测量[J].实验力学, 2009, 24(3):197-201. Wang B, Bai C R, Yang G J, et al.Measurement of transition location change of swept wing in a low speed flow based on sublimation method[J].Journal of Experimental Mechanics, 2009, 24(3):197-201(in Chinese). [16] 孙朋朋.马赫数、攻角及后掠角对后掠机翼边界层稳定性及转捩的影响[D].天津:天津大学, 2015. Sun P P.Effect of Mach number, attack angle and sweep angle on the stability and transition in a swept-wing boundary layer[D].Tianjin:Tianjin University, 2015(in Chinese). [17] 黄章峰,逯学志,于高通.机翼边界层的横流稳定性分析和转捩预测[J].空气动力学学报, 2014, 32(1):14-20. Huang Z F, Lu X Z, Yu G T.Cross-flow instability analysis and transition prediction of airfoil boundary layer[J].ACTA Aerodynamic Sinica, 2014, 32(1):14-20(in Chinese). [18] 韩步璋,黄奕裔,张其威,等.NACA0012翼型跨音速测压实验研究[J].南京航空航天大学学报, 1987, 19(2):92-102. Han B Z, Hang Y Y, Zhang Q W, et al.An experiment of pressure measurement for NACA0012 airfoil in a transonic wind tunnel[J].Journal of Nanjing Aeronautical Institute, 1987, 19(2):92-102(in Chinese). [19] Huang Z F, Cao W, Zhou H.The mechanism of breakdown in laminar-turbulent transition of a supersonic boundary layer on a flat plate-temporal mode[J].Science in China Series G:Mechanics and Astronomy, 2005, 48(5):614-625.
点击查看大图
计量
- 文章访问数: 960
- HTML全文浏览量: 74
- PDF下载量: 562
- 被引次数: 0