低雷诺数下翼面局部振动增升机理研究
收稿日期: 2014-12-23
修回日期: 2015-04-01
网络出版日期: 2015-04-15
基金资助
国家自然科学基金(11402212);中央高校基本科研业务费专项资金(3102014JCQ01002)
Lift enhancement mechanism for local oscillation of airfoil surface at low Reynolds number
Received date: 2014-12-23
Revised date: 2015-04-01
Online published: 2015-04-15
Supported by
National Natural Science Foundation of China (11402212);The Fundamental Research Funds for the Central Universities (3102014JCQ01002)
采用计算流体力学(CFD)方法研究低雷诺数下翼面局部振动对翼型气动特性及其流动特征的影响规律。建立局部振动激励的力学模型,并采用任意拉格朗日-欧拉坐标系下的特征线有限元(ALE-CBS)方法对局部振动激励下翼型绕流问题进行模拟,分析局部振动对非定常流动演化的影响规律,揭示其增升机理。研究结果表明:翼面局部变形的增加会有效降低翼型上表面的前缘压力;非定常流动分离中旋涡之间的距离及其演化频率与振动频率的关系是影响翼型翼面局部振动增升效果的重要因素。当流场主频率与振动频率相同,次要频率为主频率的2倍,即发生锁频时,翼面振动产生的移动分离泡能够使分离区从主流获取更多的能量,使翼型上表面保持较低的压力,有效提高翼型升力。
康伟 , 刘磊 , 徐敏 , 雷鹏飞 , 张家忠 . 低雷诺数下翼面局部振动增升机理研究[J]. 航空学报, 2015 , 36(11) : 3557 -3566 . DOI: 10.7527/S1000-6893.2015.0094
Aerodynamic performance and the related flow patterns are studied for low Reynolds number flow with local oscillation of airfoil surface using computational fluicl dynamics (CFD) method. The model of local oscillation of airfoil surface is established and flow around the airfoil under the oscillation is simulated by arbitrary Lagrangian Eulerian-characteristic based split (ALE-CBS) algorithm. The effect of the local oscillation on flow evolution is highlighted to reveal the mechanism for lift enhancement. The results show that the local deformation of the surface reduces the suction pressure on the leading edge efficiently. Moreover, the crucial factors for lift enhancement of local oscillation are the distance between the vortices in the flow separation zone and the relationship between the oscillating frequencies and frequencies of vortex formation. The moving separation bubbles can transfer more energy from the main stream to keep a lower pressure on the upper surface so that the lift of the airfoil is improved effectively, as the primary frequency of flow equals the oscillating frequency and the second order frequency of the flow is twice of the first one, i.e. frequency lock-in occurs.
[1] Shyy W. Aerodynamics of low Reynolds number flyers[M]. Cambridge, UK:Cambridge University Press, 2007:1-47.
[2] Shyy W, Aono H, Chimakurthi S, et al. Recent progress in flapping wing aerodynamics and aeroelasticity[J]. Progress in Aerospace Sciences, 2010, 46(7):284-327.
[3] Ifju P G, Jenkins D A, Ettinger S, et al. Flexible-wing-based micro air vehicles, AIAA-2002-0705[R]. Reston:AIAA, 2002.
[4] Lian Y, Shyy W, Viieru D, et al. Membrane wing aerodynamics for micro air vehicles[J]. Progress in Aerospace Sciences, 2003, 39(6-7):425-465.
[5] O'Meara M, Mueller T. Laminar separation bubble characteristics on an airfoil at low Reynolds numbers[J]. AIAA Journal, 1987, 25(8):1033-1041.
[6] Shyy W, Berg M, Ljungqvist D. Flapping and flexible wings for biological and micro air vehicles[J]. Progress in Aerospace Sciences, 1999, 35(5):455-505.
[7] Sinha S K, Ravande S V. Drag reduction of natural laminar flow airfoils with a flexible surface deturbulator, AIAA-2006-3030[R]. Reston:AIAA, 2006.
[8] Zhan P G, Cheng Y H, Zhao X. Active flow control technique[J]. Aeronautical Science and Technology, 2010(5):2-6(in Chinese).战培国,程娅红,赵昕.主动流动控制技术研究[J].航空科学技术, 2010(5):2-6.
[9] Song A, Breuer K. Dynamics of a compliant membrane as related to mammalian flight, AIAA-2007-0665[R]. Reston:AIAA, 2007.
[10] Taylor G, Kroker A, Gursul I. Passive flow control over flexible non-slender delta wings[C]//43rd AIAA Aerospace Sciences Meeting and Exhibit. Reston:AIAA, 2005:14389-14405.
[11] Zhang M, Zhou Y, Cheng L. Control of poststall airfoil aerodynamics based on surface perturbation[J]. AIAA Journal, 2008, 46(10):2510-2519.
[12] Kang W, Zhang J Z. Numerical analysis of lift enhancement and drag reduction by self-induced vibration of localized elastic airfoil[J]. Journal of Xi'an Jiaotong University, 2011, 45(5):94-101(in Chinese).康伟,张家忠.翼型局部弹性自振动动的增升减阻效应研究[J].西安交通大学学报, 2011, 45(5):94-101.
[13] Kang W, Zhang J Z, Feng P H. Aerodynamic analysis of a localized flexible airfoil at low Reynolds numbers[J]. Communications in Computational Physics, 2012, 11(4):1300-1310.
[14] Kang W, Zhang J Z, Lei P F, et al. Computation of unsteady viscous flow around a locally flexible airfoil at low Reynolds number[J]. Journal of Fluids and Structures, 2014, 46:42-58.
[15] Kang W, Zhang J Z, Ren S, et al. Nonlinear Galerkin method for low-dimensional modeling of fluid dynamic system using POD modes[J]. Communications in Nonlinear Science and Numerical Simulation, 2015, 22(1):943-952.
[16] Lei P F, Zhang J Z, Chen J H. Unsteady separation of flow around airfoil with local elastic structure[J]. Chinese Journal of Theoretical and Applied Mechanics, 2012, 44(1):13-22(in Chinese).雷鹏飞,张家忠,陈嘉辉.局部弹性翼型非定常分离的动力学特性[J].力学学报, 2012, 44(1):13-22.
[17] Zienkiewicz O C, Codina R. A general algorithm for compressible and incompressible-flow 1. The split, characteristic-based scheme[J]. International Journal for Numerical Methods in Fluids, 1995, 20(8-9):869-885.
[18] Zienkiewicz O C, Morgan K, Sai B V K S, et al. A general algorithm for compressible and incompressible-flow 2. Tests on the explicit form[J]. International Journal for Numerical Methods in Fluids, 1995, 20(8-9):887-913.
[19] Zienkiewicz O C, Nithiarasu P, Codina R, et al. The characteristic-based-split procedure:an efficient and accurate algorithm for fluid problems[J]. International Journal for Numerical Methods in Fluids, 1999, 31(1):359-392.
[20] Batina J T. Unsteady Euler algorithm with unstructured dynamic mesh for complex-aircraft aerodynamic analysis[J]. AIAA Journal, 1991, 29(3):327-333.
[21] Blom F J. Considerations on the spring analogy[J]. International Journal for Numerical Methods in Fluids, 2000, 32(6):647-668.
[22] Bathe K J, Zhang H. A mesh adaptivity procedure for CFD and fluid-structure interactions[J]. Computers & Structures, 2009, 87(11-12):604-617.
/
| 〈 |
|
〉 |
CJA