Regarding the issue about Hybrid Laminar Flow Control (HLFC) wings aerodynamic design, we establish an aerodynamic optimization design system by directly coupling the CFD method with the optimization technologies including the Free Form Deformation (FFD) parameterization, the Radial Basis Function (RBF) dynamic mesh method based on compact support radial basis function, and the improved differential evolution. The transition prediction model is eN method. For the infinite span swept wing, the system proposed is used to do single-point design, and multi-point robust designs which consider the variation of lift coefficients and Mach numbers. Optimization results show that the best pressure distribution of HLFC wings has a low negative pressure peak at the leading edge, followed by a gently adverse pressure gradient. Then, just behind the adverse pressure gradient, there exists a suitable favorable pressure gradient. Compared with the original model, the transition location of the single-point design result, which has a good pressure distribution, is delayed from 2% of the chord to the chord length of 57%, but the suction control strength is only half of that of the original model. Multi-point design results indicate that increasing the strength of suction control, especially at the beginning and end of the suction control region, is conducive to improving the robustness of HLFC wings. When the Mach number is in the range of 0.77-0.79 and the lift coefficient is in the range of 0.53-0.65, the multi-point design results can maintain laminar flow region over the chord length of 37%.
[1] SCHRAUF G. Status and perspectives of laminar flow[J]. Aeronautical Journal, 2005, 109(1102):639-644.[2] 朱自强, 吴宗成, 丁举春. 层流流动控制技术及应用[J]. 航空学报, 2011, 32(5):765-784. ZHU Z Q, WU Z C, DING J C. Laminar flow control technology and application[J]. Acta Aeronautica et Astronautica Sinica, 2011, 32(5):765-784(in Chinese).[3] REED H L, SARIC W S. Transition mechanisms for transport aircraft:AIAA-2008-3743[R]. Reston,VA:AIAA, 2008.[4] FUJINO M. Design and development of the HondaJet[J]. Journal of Aircraft, 2005, 42(3):755-764.[5] 朱自强, 鞠胜军, 吴宗成. 层流流动主/被动控制技术[J]. 航空学报, 2016, 37(7):2065-2090. ZHU Z Q, JU S J, WU Z C. Laminar flow active/passive control technology[J]. Acta Aeronautica et Astronautica Sinica, 2016, 37(7):2065-2090(in Chinese).[6] WASSERMANN P, KLOKER M. Mechanisms and passive control of crossflow-vortex-induced transition in a three-dimensional boundary layer[J]. Journal of Fluid Mechanics, 2002, 456:49-84.[7] SAEED T I, GRAHAM W R, HALL C A. Boundary-layer suction system design for laminar-flying-wing aircraft[J]. Journal of Aircraft, 2011, 48(4):1368-1379.[8] RISSE K, SCHUELTKE F, STUMPF E, et al. Conceptual wing design methodology for aircraft with hybrid laminar flow control:AIAA-2014-0023[R]. Reston,VA:AIAA, 2014.[9] 黄江涛, 高正红, 白俊强, 等. 应用Delaunay图映射与FFD技术的层流翼型气动优化设计[J]. 航空学报, 2012, 33(10):1817-1826. HUANG J T, GAO Z H, BAI J Q, et al. Laminar airfoil aerodynamic optimization design based on Delaunay graph mapping and FFD technique[J]. Acta Aeronautica et Astronautica Sinica, 2012, 33(10):1817-1826(in Chinese).[10] ZHANG Y F, FANG X M, CHEN H X, et al. Supercritical natural laminar flow airfoil optimization for regional aircraft wing design[J]. Aerospace Science and Technology, 2015, 43:152-164.[11] SHI Y Y, BAI J Q, HUA J, et al. Numerical analysis and optimization of boundary layer suction on airfoils[J]. Chinese Journal of Aeronautics, 2015, 28(2):357-367.[12] 耿子海, 刘双科, 王勋年, 等. 二维翼型混合层流控制减阻技术试验研究[J]. 实验流体力学, 2010, 24(1):16-50. GENG Z H, LIU S K, WANG X N, et al. Test study of drag reduction technique by hybrid laminar flow control with two-dimension airfoil[J]. Journal of Experiments in Fluid Mechanics, 2010, 24(1):16-50(in Chinese).[13] 朱心雄. 自由曲线曲面造型技术[M].北京:科学出版社, 2008:236-238. ZHU X X. Free-surface modeling techniques[M]. Beijing:Science Press, 2008:236-238(in Chinese).[14] 林言中, 陈兵, 徐旭. 径向基函数插值方法在动网格技术中的应用[J]. 计算物理, 2012, 29(2):191-197. LIN Y Z, CHEN B, XU X. Radial basis function interpolation method in dynamic grid application[J]. Chinese Journal of Computational Physics, 2012, 29(2):191-197(in Chinese).[15] DRAKE A, SOLOMON W D. Flight testing of a 30-degree sweep laminar flow wing for a high-altitude long-endurance aircraft:AIAA-2010-4571[R]. Reston,VA:AIAA, 2010.[16] MACK L M. Boundary-layer linear stability theory[R]. Brussels:AGARD, 1984.[17] KLTZSCHE M, PEARCE W, MCNAY D, et al. Laminar flow control leading edge glove/flight test article development:NASA-CR-172137[R]. Washington,D.C.:NASA, 1984.[18] DAGENHART J R,SARIC W S.Crossflow stability and transition experiments in swept-wing flow:NASA-1999-209344[R]. Washington, D.C.:NASA,1999.[19] LANGTRY R B,MENTER F R.Correlation-based transition modeling for unstructured parallelized computational fluid dynamics codes[J].AIAA Journal,2009,47(12):2894-2906.[20] 白俊强, 刘南, 邱亚松, 等. 基于RBF动网格方法和改进粒子群优化算法的多段翼型优化[J]. 航空学报, 2013, 34(12):2701-2715. BAI J Q, LIU N, QIU Y S, et al. Optimization of multi-foil based on RBF mesh deformation method and modified particle swarm optimization algorithm[J]. Acta Aeronautica et Astronautica Sinica, 2013, 34(12):2701-2715(in Chinese).[21] 赵光权. 基于贪婪策略的微分进化算法及其应用研究[D].哈尔滨:哈尔滨工业大学, 2007. ZHAO G Q. Differential evolution algorithm based on greedy strategy and its application[D]. Harbin:Harbin Institute of Technology, 2007(in Chinese).[22] 苏海军, 杨煜普, 王宇嘉. 微分进化算法的研究综述[J].系统工程与电子技术, 2008, 30(9):1793-1797. SUN H J, YANG Y P, WANG Y J. Research on differential evolution algorithm:A survey[J]. Systems Engineering and Electronics, 2008, 30(9):1793-1797(in Chinese).[23] 杨体浩, 白俊强, 王丹, 等. 考虑发动机干扰的尾吊布局后体气动优化设计[J].航空学报,2014,35(7):1836-1844. YANG T H, BAI J Q, WANG D, et al. Aerodynamic optimization design for after-body of tail-mounted engine layout considering interference of engines[J]. Acta Aeronautica et Astronautica Sinica, 2014, 35(7):1836-1844(in Chinese).
CJA