飞行失控是造成民机灾难性航空事故的重要因素，飞行失控中飞机难以避免超出正常飞行包线范围，进入具有复杂非线性和非定常动态气动特性的极限飞行状态。本文开展典型民机布局飞机极限飞行状态的动导数、大振幅试验，对大迎角动态气动力的参数影响规律以及非线性、非定常特性进行分析和建模。结果表明，在飞机失速到过失速区域，飞行姿态快速变化过程中动态气动力的非线性和非定常特征显著；在动导数试验和建模中，考虑运动角速率的影响，可以预示气动力非线性的迎角范围，并捕捉到关于飞机动稳定性演化的关键特征；利用Goman-Khrabrov状态空间模型结合大振幅试验，可以确定模型中表征非定常特征的关键时间常数，获得特定极限飞行状态运动中的非定常动态气动力特性。研究方法和结果为开展民机极限飞行状态的动态气动力风洞试验设计与建模提供了一个可行途径，能改进飞机飞行失控预防、极限状态改出、飞行模拟训练和飞行事故分析等。
Loss of control is an important cause of catastrophic aviation accidents, possibly exposing the aircraft under extreme flight conditions with complex nonlinear and unsteady aerodynamic characteristics beyond the normal flight envelope. The dynamic derivative and large amplitude wind tunnel tests under the extreme flight conditions are conducted to analyze the impact factors for dynamic aerodynamics and the nonlinear and unsteady characteristics. Results show that the nonlinear and unsteady characteristics of dynamic aerodynamics are significant in stall to incipient spin regions; for dynamic derivative test and modeling, the impact of the angular velocity of motion can be considered to predict the range of angle of attack of aerodynamic nonlinearity and capture the key characteristics related to the dynamic stability of flight maneuvers; using the Goman-Khrabrov state space model combined with the large amplitude test, the key time constants of the unsteady characteristics in the model can be determined, and the unsteady aerodynamic characteristics in the specific extreme flight state motion can be obtained. The research methods and results provide a promising way for the design and modeling of the dynamic aerodynamic test of civil aircraft under extreme flight conditions.
[1] CAST/ICAO Common Taxonomy Team. Aviation occurrence categories:Definitions and usage notes[EB/OL]. (2017-12-31)[2019-11-10].http://www.intlaviationstandards.org/Documents/OccurrenceCategoryDefinitions.pdf.
[2] Boeing Aviation Safety Group. Statistical summary of commercial jet airplane accidents, worldwide operations, 1959-2017[EB/OL]. (2017-10-31)[2019-11-10]. http://www.boeing.com/resources/boeingdotcom/company/about_bca/pdf/statsum.pdf.
[3] BELCASTRO C M, FOSTER J V, SHAH G H, et al. Aircraft loss of control problem analysis and research toward a holistic solution[J]. Journal of Guidance, Control, and Dynamics, 2017, 40(4):733-775.
[4] 伍开元. 民机空难相关非定常气动力问题研究[J]. 流体力学实验与测量, 2003, 17(2):1-9. WU K Y. Unsteady aerodynamics in fatal accidents[J]. Experiments and Measurements in Fluid Mechanics, 2003, 17(2):1-9(in Chinese).
[5] 汪清, 钱炜祺, 丁娣. 飞机大迎角非定常气动力建模研究进展[J]. 航空学报, 2016, 37(8):2331-2347. WANG Q, QIAN W Q, DING D. A review of unsteady aerodynamic modeling of aircrafts at high angle of attack[J]. Acta Aeronautica et Astronautica Sinica, 2016, 37(8):2331-2347(in Chinese).
[6] 孙海生, 姜裕标, 黄勇, 等. 现代战斗机非定常空气动力学及其风洞实验研究[J]. 空气动力学学报, 2008, 26(增刊):59-65. SUN H S, JIANG Y B, HUANG Y, et al. Unsteady aerodynamics of modern fighter plane and experiment research in W.T.[J]. Acta Aerodynamica Sinica, 2008, 26(Supplement):59-65(in Chinese).
[7] KALVISTE J. Use of rotary balance and forced oscillation test data in six degrees of freedom simulation[C]//9th AIAA Atmospheric Flight Mechanics Conference. Reston:AIAA, 1982.
[8] ETKIN B, REID L D. Dynamics of atmospheric flight:stability and control[M]. New York:John Wiley& Sons Inc, 1972:264-293.
[9] TOBAK M, SCHIFF L B. Aerodynamic mathematical modelling-basic concepts:AGARD LS-114[R]. 1981.
[10] GOMAN M, KHRABROV A. State-space representation of aerodynamic characteristics of an aircraft at high angles of attack[J]. Journal of Aircraft, 1994, 31(5):1109-1115.
[11] 汪清, 蔡金狮. 飞机大攻角非定常气动力建模与辨识[J]. 航空学报, 1996,17(4):391-398. WANG Q, CAI J S. Unsteady aerodynamic modeling and identification of airplane at high angles of attack[J]. Acta Aeronautica et Astronautica Sinica, 1996,17(4):391-398(in Chinese).
[12] 龚正, 沈宏良. 非定常气动力的结构自适应神经网络建模方法[J]. 飞行力学, 2007, 25(4):13-16. GONG Z, SHEN H L. Structure self-adapting ANN method in modeling of unsteady aerodynamics[J]. Flight Dynamics, 2007, 25(4):13-16(in Chinese).
[13] WANG Z, LAN C E, BRANDON J. Fuzzy logic modeling of nonlinear unsteady aerodynamics[C]//23rd AIAA Atmospheric Flight Mechanics Conference. Reston:AIAA, 1998.
[14] WANG Q, QIAN W Q, HE K F. Unsteady aerodynamic modeling at high angles of attack using support vector machines[J]. Chinese Journal of Aeronautics, 2015,28(3):659-668.
[15] GOMAN M, KHRABROV A, USOLTSEV S P. Unsteady aerodynamic model for large amplitude maneuvers and its parameter identificaton[C]//The Inernational Federation of Automatic Control, 11th IFAC Symposium on System Identification. Kitakyushu:IFAC,1997.
[16] SMITH M S. Analysis of wind tunnel oscillatory data of the X-31A aircraft:NASA CR-1999-208725[R]. Washington, D.C.:NASA, 1999.
[17] 汪清, 何开锋, 钱炜祺,等. 飞机大迎角空间机动气动力建模研究[J]. 航空学报, 2004,25(5):447-451. WANG Q, HE K F, QIAN W Q, et al. Aerodynamic modeling of spatial maneuvering aircraft at high angle of attack[J]. Acta Aeronautica et Astronautica Sinica, 2004,25(5):447-451(in Chinese).
[18] BRANDON J M, FOSTER J V, SHAH G H, et al. Comparison of rolling moment characteristics during roll oscillation for a low and a high aspect ratio configuration[C]//2004 AIAA Atmospheric Flight Mechanics Conference and Exhibit. Reston:AIAA, 2004.
[19] Industry Airplane Upset Recovery Training Aid Team. Airplane upset recovery training aid, Rev. 2[M]. Virginia:Flight Safety Foundation, 2008:368-379.
[20] RIVERS M. Common research model[EB/OL]. (2012-02-10)[2018-10-10].https://commonresearchmodel.larc.nasa.gov/geometry/.
[21] ATINAULT O, HUE D. Design of a vertical tail for the CRM configuration:RT 1/21960 GMT/DAAP[R]. Châtillon Cedex:ONERA, 2014.
[22] VASSBERG J, DEHAAN M A, RIVERS M. Development of a common research model for applied CFD validation studies[C]//26th AIAA Applied Aerodynamics Conference. Reston:AIAA, 2008.
[23] 李周复. 风洞特种试验技术[M]. 北京:航空工业出版社, 2010:208-209. LI Z F. Special test techniques in wind tunnel[M]. Beijing:Aircraft Industry Press, 2010:208-209(in Chinese).
[24] PASHILKAR A A, PRADEEP S. Unsteady aerodynamic modelling using multivariate orthogonal polynomials:AIAA-1999-4014[R]. Reston:AIAA, 2013.
[25] FAN Y G, LUTZE F H. Identification of an unsteady aerodynamic model at high angles of attack:AIAA-1996-3407[R]. Reston:AIAA, 1996.
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