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Performance characteristics of single rotor compound helicopter
CAO Fei, CHEN Ming
School of Aeronautic Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083, China
Abstract: In order to analysis the performance of the compound helicopter, a performance calculation model consisting of all the aerodynamics mathematical model parts is established. Based on the calculation model, using various flight conditions, we constructed the compound helicopter transition flight border, studied the characteristic variation of flight power from hover flight mode to high-speed flight mode by selecting different routes, and investigated the effects of multiple factors including rotor speed, forward speed, rotor and wing loading distribution in high-speed mode. The results indicated that the reduction of flight power could be achieved by increasing the offload lift from the rotor to the wing; moreover, it was more effective to reduce the rotor speed than reduce the rotor collective pitch, during the compound helicopter transits from hover mode to high-speed mode. The rotor could not operate at very low speed, which might increase the power consumption during high-speed flight mode. Furthermore, the low rotor speed could also influence the trim of the aircraft model, and made its calculation iteratively divergent.
Key words: compound helicopter     mathematical model     transition border     power     offload

1 复合式直升机模型建立

1.1 旋翼模型

1.2 机翼模型

1.3 其他模型

 图 1 复合式直升机三维模型 Fig. 1 3D model of compound helicopter

 名称 参数 名称 参数 旋翼半径R/m 1.2 机翼翼展 2R 旋翼弦长 0.07R 机翼展弦比 10 旋翼桨叶片数 2 尾桨直径 0.35R 旋翼桨毂形式 跷跷板式 尾桨桨叶片数 4 螺旋桨直径 0.42R 垂尾展长 0.5R 螺旋桨桨叶片数 4 平尾展长 0.65R 旋翼翼型 NACA0012 尾桨扭转角/(°) 0 机翼翼型 NACA4412 旋翼扭转角/(°) 0 尾桨翼型 NACA0012 螺旋桨扭转角/(°) 0 质量/kg 40 阻力面积/m2 0.065
1.4 复合式直升机模型配平

2 过渡飞行功率特性

2.1 过渡飞行边界

 图 2 复合式直升机过渡飞行边界 Fig. 2 Compound helicopter transition border
2.2 恒定转速过渡飞行功率变化

 图 3 不同过渡路线飞行需用功率与前飞速度关系 Fig. 3 Relationship between flight need power and forward speed on different transition routes
 图 4 不同过渡路线飞行需用功率与旋翼总距关系 Fig. 4 Relationship between flight need power and collective pitch of rotor on different transition routes

 图 5 机翼和旋翼升阻比 Fig. 5 Lift to drag ratio of wing and rotor
 图 6 不同过渡路线下的机翼迎角和旋翼总距 Fig. 6 Angle of attack of wing and collective pitch of rotor on different transition routes
 图 7 不同过渡路线下的旋翼、机翼升力 Fig. 7 Lift of rotor and wing on different transition routes
 图 8 不同过渡路线下的旋翼和螺旋桨需用功率 Fig. 8 Need power of rotor and propeller on different transition routes

ABF路线需用功率在B点拐折后的变化是由于飞机从最小前飞速度边界进入最小旋翼总距边界后,旋翼总距提高和机翼攻角降低使二者的升阻比有一定的提高,导致飞机的需用功率随前飞速度增长有一定的减缓。AEF路线需用功率发生拐折后的变化是由于飞机进入EF段后,前飞速度是不变的,旋翼随着总距的减小开始卸载使得旋翼阻力降低,旋翼需用功率降低,此时飞机通过旋翼卸载损失的升力是由机翼改变迎角补偿的,而机翼升阻特性在前飞速度不变时随迎角的变化正是这种先增大后减小的变化,因此也是引起AEF路线的需用功率在E点后又一次发生先减小后增大的原因。

2.3 变转速过渡飞行功率变化

 图 9 不同旋翼转速下的过渡飞行边界 Fig. 9 Transition borders at different rotor speeds

 图 10 AF路线在不同旋翼转速下的需用功率 Fig. 10 AF route need power at different rotor speeds
3 旋翼转速、前飞速度以及旋翼和机翼升力分配关系的影响

 图 11 旋翼需用功率随旋翼总距变化曲线 Fig. 11 Rotor need power change curves with collective

 图 12 旋翼和机翼升力在不同前飞速度下的变化 Fig. 12 Lift of rotor and wing change with different forward speeds

 图 13 1°旋翼总距下机翼安装角和机翼需用功率随 前飞速度变化 Fig. 13 Wing angle of incidence and need power change with forward speed at 1°collective pitch of rotor

 图 14 1°旋翼总距下旋翼和机翼需用功率随前飞速度变化 Fig. 14 Need power of rotor and wing change with forward speed at 1°collective pitch of rotor
4 结 论

1) 复合式直升机在过渡飞行时,其飞行需用功率变化主要受机翼与旋翼升阻特性影响,而影响比重与两者承担升力的大小有关。

2) 在过渡飞行边界内,其最小需用功率飞行状态点处于旋翼与机翼共同承担升力的状态下,而不是单独由旋翼或者机翼承担全部升力。

3) 为提高前飞速度,降低飞行需用功率,通过降低旋翼转速卸载比恒定转速降低旋翼总距卸载的效果更好。

4) 复合式直升机进入高速飞行后,降低旋翼转速可降低旋翼需用功率,但旋翼转速受升力分配关系影响,只有机翼与旋翼的升力随前飞速度变化是基本恒定的旋翼转速,才能满足复合式直升机高速飞行的需求。

5) 在整个飞行过程中,旋翼转速过低,也会因为反流区和后行桨叶失速问题引起飞行需用功率增加和模型配平不收敛。

 [1] 倪先平. 未来直升机技术发展展望[J].航空制造技术,2008(3):32-37. NI X P.Outlook of future helicopter technology[J].Aeronautical Manufacturing Technology,2008(3):32-37(in Chinese). Cited By in Cnki (561) [2] MARKS M D. Flight test development of the XV-1 convertiplane[J].Journal of the American Helicopter Society,1957,2(1) :55-65. Click to display the text [3] MOODIE A M, YEO H.Design of a cruise-efficient compound helicopter[J].Journal of the American Helicopter Society,2012,57(3):032004-1-032004-11. Click to display the text [4] VU N A, LEE Y J,LEE J W,et al.Configuration design and optimisation study of a compound gyroplane[J].Aircraft Engineering and Aerospace Technology,2011,83(6):420-428. Click to display the text [5] YEO H, JOHNSON W.Optimum design of a compound helicopter[J].Journal of Aircraft,2006,46(4):1210-1221. Click to display the text [6] FLOROS M W, JOHNSON W.Stability and control analysis of the slowed-rotor compound helicopter[J].Journal of the American Helicopter Society,2007,52(3):239-253. Click to display the text [7] YEO H, JOHNSON W.Aeromechanics analysis of heavy lift slowed rotor compound helicopter[J].Journal of Aircraft,2007,44(2):501-508. Click to display the text [8] FERGUSON K, THOMSON D.Flight dynamics investigation of compound helicopter configurations[J].Journal of Aircraft,2015,52(1):156-167. Click to display the text [9] 韩东. 变转速旋翼直升机性能及配平研究[J].航空学报,2013,34(6):1241-1248. HAN D.Study on the performance and trim of helicopter with variable speed rotor[J].Acta Aeronautica et Astronautica Sinica,2013,34(6):1241-1248(in Chinese). Cited By in Cnki (411) [10] 徐明,韩东, 李建波.变转速旋翼气动特性分析及试验研究[J].航空学报,2013,34(9):2047-2056. XU M,HAN D,LI J B.Analysis and experimental investigation on the aerodynamic characteristics of variable speed rotor[J].Acta Aeronautica et Astronautica Sinica,2013,34(9):2047-2056(in Chinese). Cited By in Cnki (230) [11] 万佳,陈铭. 机翼位置对复合式直升机旋翼-机翼干扰的影响[J].北京航空航天大学学报,2009,35(5):519-522. WAN J,CHEN M.Influence of wing location on rotor-wing interaction of compound helicopter[J].Journal of Beijing University of Aeronautics and Astronautics,2009,35(5):519-522(in Chinese). Cited By in Cnki (202) [12] 朱凌军. 复合式高速直升机悬停状态旋翼/机翼气动干扰研究[D].南京:南京航空航天大学,2005:42-52. ZHU L J.Investigation on wing-rotor aerodynamic interaction of the compound helicopter in hover[D].Nanjing:Nanjing University of Aeronautics and Astronautics,2005:42-52(in Chinese). Cited By in Cnki (449) [13] PETERS D A, HAQUANG N.Dynamic inflow for practical applications[J].Journal of the American Helicopter Society,1988,33(4):64-68. Click to display the text [14] JOHNSON W. Helicopter theory[M].Dover:Dover Publications Inc.,1995:455-459. [15] DREIER M E. Introduction to helicopter and tiltrotor flight simulation[M].Reston:AIAA,2007:149-165.

#### 文章信息

CAO Fei, CHEN Ming

Performance characteristics of single rotor compound helicopter

Journal of Beijing University of Aeronautics and Astronsutics, 2016, 42(4): 772-779.
http://dx.doi.org/10.13700/j.bh.1001-5965.2015.0267