Mechanism effect of circling parameters on the helicopter unsteady blade/vortex interaction
-
摘要:
开展了盘旋飞行参数对旋翼非定常桨/涡干扰特性的影响规律研究。建立了考虑桨叶挥舞以及盘旋修正的旋翼桨尖涡高效准确模拟自由尾迹方法，机身与尾桨载荷求解基于风洞试验数据进行数值拟合。在此基础上构建了兼顾效率与精度的全机配平方法。在配平条件下对不同盘旋状态的旋翼涡尾迹分布及气动载荷开展模拟，揭示了盘旋飞行参数对非定常桨/涡干扰特性的影响机理。结果表明：小速度小半径盘旋时，部分尾迹涡段在桨盘下方方位角${ \varPsi=60{\text {°}}} $后开始弯曲畸变，并在方位角$ {\varPsi =90{\text {°}}} $后卷入盘旋方向内侧的桨盘上方附近区域，在一定的相位区间内形成桨叶与多段涡元的连续集中干扰，导致了垂向诱导速度的快速变化，气动载荷在小范围内产生突变；盘旋方向不影响桨/涡干扰的影响机理，但会改变气动载荷的谐波特点，1阶气动载荷对盘旋方向的敏感性最强；随着盘旋半径的增加，桨盘上方集中干扰现象受尾迹畸变的减弱快速消失，桨盘范围内的其他扰动逐渐突出，使气动载荷的分布沿周向移动，5阶以上气动载荷衰减极快，低阶气动载荷随盘旋半径的影响范围较宽；盘旋速度的增加使得尾迹涡在空间分布上拉伸，削弱了桨/涡干扰现象，各阶气动载荷呈一致变化趋势。
Abstract:The influences of circling flight parameters on the unsteady blade/vortex interaction characteristics were studied comprehensively. An efficient and accurate simulation method for the blade tip vortex considering flapping and circling correction was established. The airloads of the fuselage and tail rotor were calculated by the numerical fitting of wind tunnel test data. Based on this, a comprehensive trim method of balancing the efficiency and accuracy was constructed. Afterwards, under the trim condition, the distributions of the rotor wake and aerodynamic loads in different circling states were simulated, revealing the influence mechanism of circling flight parameters on the unsteady blade/vortex interaction characteristics. The results showed that the vortex was distorted under rotor disc after $ \varPsi $=60° and certain segments of the vortex rolled into the region above the rotor disc after $\varPsi $=90° on the inner side of the circling direction with low circling speed and small radius. The resulting continuous and concentrated interaction led to rapid changes in the vertical induced velocity, causing abrupt changes in local aerodynamic loads. The circling direction did not affect the influence mechanism of blade/vortex interaction. Instead, it affected the harmonic characteristics of aerodynamic load and the first order component was most sensitive to the circling direction. With the increase of circling radius, the weakening of wake distortion led to the rapid disappearance of the concentrated interaction phenomenon above rotor disc. Other interactions within the rotor disc became prominent gradually, causing the distribution of aerodynamic loads to move along the circumferential direction. As for the circling radius, the aerodynamic loads above the fifth order fell out fast, and the influence range of lower order aerodynamic loads was wider than higher order parts. The increase in circling speed stretched the wake vortex, weakening the blade/vortex interaction phenomenon in spatial distribution. The aerodynamic loads of each order showed the same changing trend.
-
Key words:
- helicopter /
- circling flight /
- blade/vortex interaction /
- free wake /
- aerodynamic load /
- discrete Fourier transform
-
图 1 前飞与盘旋飞行状态的初始尾迹对比
Figure 1. Comparison of initial wakes between forward flight and circling flight
图 3 UH-60A桨叶负扭及翼型分布
Figure 3. Twist angle and airfoil distribution of UH-60A helicopter rotor blades
图 8 盘旋时的尾迹、气动载荷及其时间偏导分布（$ {\mu } {=0.04} $, Rcir=8 m）
Figure 8. Distribution of free wake, aerodynamic load, and its partial derivation with respect to time at circling flight （$ {\mu } {=0.04} $, Rcir=8 m）
图 9 左盘旋时的尾迹、气动载荷分布（$ {\mu } {=0.04} $, Rcir=8 m）
Figure 9. Distribution of free wake, aerodynamic load with respect to time at rotor disc when circling leftwards （$ {\mu } {=0.04} $, Rcir=8 m）
图 10 左盘旋时桨盘下方流场垂向速度分布（$ {\mu } {=0.04} $, Rcir=8 m）
Figure 10. Distribution of vertical velocity under rotor disc when circling leftwards （$ {\mu } {=0.04} $, Rcir=8 m）
图 11 左盘旋时的尾迹、气动载荷分布（$ {\mu } {=0.18} $, Rcir=100 m）
Figure 11. Distribution of free wake, aerodynamic load with respect to time at rotor disc when circling leftwards （ $ {\mu } {=0.18} $, Rcir=100 m）
图 12 右盘旋时的尾迹、气动载荷分布（$ {\mu } {=0.18} $, Rcir=100 m）
Figure 12. Distribution of free wake, aerodynamic load with respect to time at rotor disc when circling leftwards （$ {\mu } {=0.18} $, Rcir=100 m）
图 13 桨盘下方流场垂向速度分布对比（$ {\mu } {=0.18} $, Rcir=100 m）
Figure 13. Comparison of vertical velocity distribution under rotor disc （$ {\mu } {=0.18} $, Rcir=100 m）
图 14 桨盘处法向力系数（$ { {Ma}}^{ {2}}{ {C}}_{\rm {n}} $）随盘旋半径的分布变化
Figure 14. Distribution of normal force coefficient （$ { {Ma}}^{ {2}}{ {C}}_{\rm {n}} $） at rotor disc with different circling radii
图 15 桨盘处气动载荷时间偏导数（$ {{\mathrm{d}}}{ {C}}_{\rm {n}} /{\mathrm{d}}\varPsi $）随盘旋半径的分布变化
Figure 15. Partial derivation of aerodynamic load with respect to time （${{\mathrm{d}}}{ {C}}_{\rm {n}} /{\mathrm{d}}\varPsi $） with different circling radii
图 16 两方向盘旋时各阶气动载荷幅值对比
Figure 16. Comparison of aerodynamic load at different orders when circling towards different directions
图 17 各阶气动载荷幅值随盘旋半径的变化（r/R=0.96, μ=0.04）
Figure 17. Variation of aerodynamic load at different orders with circling radii （r/R=0.96, μ=0.04）
图 18 各阶气动载荷幅值随盘旋速度的变化（r/R=0.96, Rcir=100 m）
Figure 18. Variation of aerodynamic load at different orders with circling velocities （r/R=0.96, Rcir=100 m）
表 1 UH-60A直升机旋翼桨叶参数
Table 1. Parameters of UH-60A main rotor
参数 数值 桨叶片数 4 旋翼半径/m 8.178 弦长/m 0.527 旋翼转速/（r/min） 258 挥舞铰偏置/m 0.381 
下载: 导出CSV
-
[1] POLING D R,DADONE L,TELIONIS D P. Blade-vortex interaction[J]. AIAA Journal,1989,27(6): 694-699. doi: 10.2514/3.10167 [2] WANG Wei,LI Dongsheng,LIU Chun. Helicopter flight simulation trim in the coordinated turn with the hybrid genetic algorithm[J]. Proceedings of the Institution of Mechanical Engineers: Part G Journal of Aerospace Engineering,2019,233(3): 1159-1168. doi: 10.1177/0954410017745899 [3] CARADONNA F X,LAUB G H,TUNG C. An experimental investigation of the parallel blade-vortex interaction[R]. NASA-TM-86005,1984. [4] HOAD D R. Helicopter blade-vortex interaction location: scale-model acoustics and free-wake analysis results[R]. NASA-TP-2658,1987. [5] BIAN Wei,ZHAO Guoqing,CHEN Xi,et al. High-fidelity simulation of blade vortex interaction of helicopter rotor based upon TENO scheme[J]. Chinese Journal of Aeronautics,2023,36(10): 275-292. doi: 10.1016/j.cja.2023.06.019 [6] JOON W L,YUNG H Y,WAYNE J. Calculation of rotor blade-vortex interaction airloads using a multiple-trailer free-wake model[J]. Journal of Aircraft,2003,40(6): 1123-1130. doi: 10.2514/2.7200 [7] ZHAO Qijun,XU Guohua,ZHAO Jinggen. New hybrid method for predicting the flowfields of helicopter rotors[J]. Journal of Aircraft,2006,43(2): 372-380. doi: 10.2514/1.14863 [8] ILIE M. A fully-coupled CFD/CSD computational approach for aeroelastic studies of helicopter blade-vortex interaction[J]. Applied Mathematics and Computation,2019,347: 122-142. doi: 10.1016/j.amc.2018.10.069 [9] ZHAO Yinyu,SHI Yongjie,XU Guohua. Helicopter blade-vortex interaction airload and noise prediction using coupling CFD/VWM method[J]. Applied Sciences,2017,7(4): 381. doi: 10.3390/app7040381 [10] WU Jiafeng,STALNOV O,CHEN Wangqiao,et al. Transient analysis of blade-vortex interaction noise[J]. Aerospace Science and Technology,2022,120: 107294. doi: 10.1016/j.ast.2021.107294 [11] ZHOU Xu,ZHANG Xiayang,WANG Bo,et al. Aerodynamic and structural characteristics of helicopter rotor in circling flight[J]. Chinese Journal of Aeronautics,2023,36(12): 282-296. doi: 10.1016/j.cja.2023.07.025 [12] WU J Z,MA H Y,ZHOU M D. Vorticity and vortex dynamics[M]. Berlin: Springer,2006. [13] VATISTAS G H,KOZEL V,MIH W C. A simpler model for concentrated vortices[J]. Experiments in Fluids,1991,11(1): 73-76. doi: 10.1007/BF00198434 [14] BHAGWAT M J,LEISHMAN J G. Generalized viscous vortex model for application to free-vortex wake and aeroacoustic calculations[J]. Annual Forum Proceedings-American Helicopter Society,2002,58(2): 2042-2057. [15] SQUIRE H B. The growth of a vortex in turbulent flow[J]. Aeronautical Quarterly,1965,16(3): 302-306. doi: 10.1017/S0001925900003516 [16] 李攀. 旋翼非定常自由尾迹及高置信度直升机飞行力学建模研究[D]. 南京: 南京航空航天大学,2010. LI Pan. Research on unsteady free wake of rotor and high confidence helicopter flight mechanics modeling[D]. Nanjing: Nanjing University of Aeronautics and Astronautics,2010. (in ChineseLI Pan. Research on unsteady free wake of rotor and high confidence helicopter flight mechanics modeling[D]. Nanjing: Nanjing University of Aeronautics and Astronautics, 2010. (in Chinese) [17] MILLER R H. A simplified approach to free wake analysis of a circling rotor[J]. Vertica,1982,6(2): 89-95. [18] BEDDOES T S. Representation of airfoil behavior[J]. Vertica,1983,7(2): 183-197. [19] PERDOMO O,WEI F S. On the flapping motion of a helicopter blade[J]. Applied Mathematical Modelling,2017,46: 299-311. doi: 10.1016/j.apm.2017.01.055 [20] HILBERT K B. A mathematical model of the UH-60 helicopter[R]. NASA-TM-85890,1984. [21] BIEDRON R,LEE-RAUSCH E M. Computation of UH-60A airloads using CFD/CSD coupling on unstructured meshes[R]. Virginia Beach,US: American Helicopter Society 67th Annual Forum,2011. [22] 郑君里. 信号与系统[M]. 第2版. 北京: 高等教育出版社,2000. ZHENG Junli. Signals and systems[M]. 2nd. ed. Beijing: Higher Education Press,2000. (in ChineseZHENG Junli. Signals and systems[M]. 2nd. ed. Beijing: Higher Education Press, 2000. (in Chinese) -
点击查看大图
计量
- 文章访问数: 370
- HTML浏览量: 283
- PDF量: 31
- 被引次数: 0