升力偏置对共轴刚性旋翼前飞气动特性的影响

doi:10.7527/S1000-6893.2019.22906

Abstract

Abstract: In order to analyze the influence of lift offset on the aerodynamic characteristics of coaxial rigid rotors in forward flights, a computational fluid dynamics method based on the Reynolds averaged Navier-Stokes equations is established to solve the coaxial rotor flow field. The nested grid method is used to simulate the blade motion, and the dual-time method is used for time propulsion. A high-efficiency trim strategy based on the "delta method" is adopted to trim the control pitches for coaxial rotor at different lift offset states. The validity of the method is verified by calculating the performance of Harrington-1 rotor. The aerodynamic performance and the flow field characteristics of the coaxial rigid rotor at different advance ratios and lift offset states are calculated and compared. The results show that the control pitches of the coaxial rotor are significantly different at small advance ratio, and the trimmed pitches of the dual rotors tend to be the same at high advance ratio. Under the same thrust condition, with the increase of the lift offset, the lift-drag ratio of the coaxial rotor increases first and then decreases, while the drag as the lift offset increases. At different advance ratios, the maximum lift-drag ratios correspond to different lift offsets. When the dual rotors meet with each other, the blade thrusts fluctuate impulsively. Meanwhile, since the flow field is dominated by the advancing blade, the amplitude of the thrust fluctuation of the retreating blade is larger than that of the advancing blade, and the amplitude increases with the increase of the lift offset.

Key words: rigid coaxial rotor, lift offset, rotor trim, aerodynamic characteristics, computational fluid dynamics, overset grid

CLC Number:

V211.52

LU Congling, QI Haotian, XU Guohua. Influence of lift offset on rigid coaxial rotor aerodynamic characteristics in forward flight[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2019, 40(11): 122906-122906.

References 24

[1]	CHENEY M C, JR. The ABC helicopter[J]. Journal of the American Helicopter Society, 1969, 14(4):10-19.
[2]	BAGAI A. Aerodynamic design of the X2 technology demonstrator main rotor blade[C]//64th American Helicopter Society Annual Forum, 2008:29-44.
[3]	JOHNSON W. Influence of lift offset on rotorcraft performance[R]. Washington,D.C.:Langley Research Center, 2009.
[4]	SCHMAUS J H, CHOPRA I. Aeromechanics for a high advance ratio coaxial helicopter[C]//71st American Helicopter Society Annual Forum, 2015:1-15.
[5]	SCHMAUS J H, CHOPRA I. Aeromechanics of rigid coaxial rotor models for wind-tunnel testing[J]. Journal of Aircraft, 2017, 54(4):1486-1497.
[6]	KIM H W, BROWN R E. Coaxial rotor performance and wake dyanmics in steady and manoeuvring flight[C]//62nd American Helicopter Society Annual Forum, 2006:20-40.
[7]	KIM H W, DURAISAMY K, BROWN R E. Effect of rotor stiffness and lift offset on the aeroacoustics of a coaxial rotor in level flight[C]//65th American Helicopter Society Annual Forum, 2009:1-21.
[8]	TAN J, SUN Y, BARAKOS G N. Unsteady loads for coaxial rotors in forward flight computed using a vortex particle method[J]. The Aeronautical Journal, 2018, 122(1251):693-714.
[9]	YEO H, JOHNSON W. Investigation of maximum blade loading capability of lift-offset rotors[J]. Journal of the American Helicopter Society, 2014, 59(1):293-301.
[10]	谭剑锋, 孙义鸣, 王浩文, 等共轴刚性双旋翼非定常气动干扰载荷分析[J]. 北京航空航天大学学报, 2018, 44(1):50-62. TAN J F, SUN Y M, WANG H W, et al. Analysis of rigid coaxial rotor unsteady interactional aerodynamic loads[J]. Journal of Beijing University of Aeronautics and Astronautics, 2018, 44(1):50-62(in Chinese).
[11]	PASSE B J, SRIDHARAN A, BAEDER J D. Computational investigation of coaxial rotor interactional aerodynamics in steady forward flight[C]//33rd AIAA Applied Aerodynamics Conference. Reston, VA:AIAA, 2015.
[12]	LAKSHMINARAYAN V K, BAEDER J D. High-resolution computational investigation of trimmed coaxial rotor aerodynamics in hover[J]. Journal of the American Helicopter Society, 2009, 54(4):42008.
[13]	朱正, 招启军, 李鹏. 悬停状态共轴刚性双旋翼非定常流动干扰机理[J]. 航空学报, 2016, 37(2):568-578. ZHU Z, ZHAO Q J, LI P. Unsteady flow interaction mechanism of coaxial rigid rotors in hover[J]. Acta Aeronautica et Astronautica Sinica, 2016, 37(2):568-578(in Chinese).
[14]	BARBELY N, KOMERATH N. Coaxial rotor flow phenomena in forward flight[C]//SAE 2016 Aerospace Systems and Technology Conference, 2016.
[15]	BARBELY N, NOVAK L, KOMERATH N. A study of coaxial rotor performance and flow field characteristics[C]//American Helicopter Society Specialists Meeting on Aeromechanics, 2016:1-15.
[16]	KLIMCHENKO V, SRIDHARAN A, BAEDER J D. CFD/CSD study of the aerodynamic interactions of a coaxial rotor in high-speed forward flight[C]//35th AIAA Applied Aerodynamics Conference. Reston, VA:AIAA, 2017.
[17]	QI H, XU G, LU C, et al. A study of coaxial rotor aerodynamic interaction mechanism in hover with high-efficient trim model[J]. Aerospace Science and Technology, 2019, 84:1116-1130.
[18]	叶舟, 徐国华, 史勇杰. 旋翼桨尖涡生成及演化机理的高精度数值研究[J]. 航空学报, 2017, 38(7):48-58. YE Z, XU G H, SHI Y J. High-resolution numerical research on formation and ecolution mechanism of rotor blade tip vortex[J]. Acta Aeronautica et Astronautica Sinica, 2017, 38(7):48-58(in Chinese).
[19]	祁浩天, 史勇杰, 徐国华, 等. 共轴刚性旋翼气动干扰及操纵特性分析[J]. 航空动力学报, 2017, 32(12):3004-3012. QI H T, SHI Y J, XU G H, et al. Analysis of aerodynamic interaction and trim characteristics of rigid coaxial rotor[J]. Journal of Aerospace Power, 2017, 32(12):3004-3012(in Chinese).
[20]	ROE P L. Approximate Riemann solvers, parameter vectors, and difference schemes[J]. Journal of Computational Physics, 1981, 43:357-372.
[21]	SPALART P, ALLMARAS S. A one-equation turbulence model for aerodynamic flows[C]//30th Aerospace Sciences Meeting and Exhibit. Reston, VA:AIAA, 1992.
[22]	FEIL R, RAULEDER J, CAMERON C G, et al. Aeromechanics analysis of a high-advance-ratio lift-offset coaxial rotor system[J]. Journal of Aircraft, 2019, 56(1):166-178.
[23]	HARRINGTON R D. Full-scale-tunnel investigation of the static-thrust performance of a coaxial helicopter rotor[R]. Washington,D.C.:Langley Research Center, 1951.
[24]	DINGELDEIN R C. Wind-tunnel studies of the performance of multirotor configurations[R]. Washington,D.C.:Langley Research Center, 1954.

Influence of lift offset on rigid coaxial rotor aerodynamic characteristics in forward flight

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