在绿色航空的研究中,分布式电推进(DEP)飞机因其在推进系统的高能量效率展现出巨大的应用潜力。但与传统推进方式的飞机相比,分布式电推进飞机在飞行时存在较强的气动-推进耦合现象。为探究分布式电推进飞机动力系统特性与气动-推进的耦合特性,设计了一套低成本的分布式电推进飞机气动-推进系统地面测试平台,通过地面试验,首先对动力系统的性能开展评估,随后通过地面试验结合数值模拟的方法对分布式电推进技术验证机的气动性能及其气动-推力耦合关系开展了研究。结果表明:涵道对边界层的抽吸效应使得上翼面的气流加速,导致上下翼面形成更大的压强差,使得升力增加;而升力增加引起的气动焦点后移现象,需要引起重视。研究结果为分布式电推进飞机的总体设计提供了参考。
In the research on green aviation, the Distributed Electric Propulsion (DEP) aircraft shows great application potential because of its high energy efficiency in the propulsion system. However, compared with the traditional propulsion aircraft, the DEP aircraft suffers from strong aerodynamic-propulsion coupling phenomenon in flight. To explore the power system characteristics and aerodynamic-propulsion coupling characteristics of the DEP aircraft, a set of low-cost ground test platform for the aerodynamic-propulsion system of the DEP aircraft is designed. Through the ground test, the performance of the power system is evaluated first, and then the aerodynamic performance and aerodynamic-propulsion coupling relationship of the DEP technology are studied by the ground test and numerical simulation. The results show that the boundary layer suction effect of the electric ducted fan accelerates the air flow on the upper wing, resulting in a larger pressure difference between the upper and lower wings and thus an increase of the lift. The backward movement of the aerodynamic center caused by the increase of lift should be paid attention to. The research results can provide a reference for the overall design of the DEP aircraft.
[1] 孔祥浩, 张卓然, 陆嘉伟, 等. 分布式电推进飞机电力系统研究综述[J]. 航空学报, 2018, 39(1): 021651. KONG X H, ZHANG Z R, LU J W, et al. Review of electric power system of distributed electric propulsion aircraft[J]. Acta Aeronautica et Astronautica Sinica, 2018, 39(1): 021651 (in Chinese).
[2] 黄俊, 杨凤田. 新能源电动飞机发展与挑战[J]. 航空学报, 2016, 37(1): 57-68. HUANG J, YANG F T. Development and challenges of electric aircraft with new energies[J]. Acta Aeronautica et Astronautica Sinica, 2016, 37(1): 57-68 (in Chinese).
[3] 王妙香, 王元元. 电动飞机的误解分析与研究综述[J]. 航空科学技术, 2019, 30(5): 3-8. WANG M X, WANG Y Y. Review on misconceptions of electric propulsion aircraft analysis and research[J]. Aeronautical Science & Technology, 2019, 30(5): 3-8 (in Chinese).
[4] STOLL A M, BEVIRT J, MOORE M D, et al. Drag reduction through distributed electric propulsion: AIAA-2014-2851[R]. Reston: AIAA, 2014.
[5] STEINER H J, SEITZ A, WIECZOREK K, et al. Multi-disciplinary design and feasibility study of distributed propulsion systems[C]//28th International Congress of the Aeronautical Sciences,2012: 23-28.
[6] KO A, SCHETZ J A, MASON W H. Assessment of the potential advantages of distributed-propulsion for aircraft: ISABE-2003-1094[R]. Reston: AIAA, 2003.
[7] HOOVER C B, SHEN J W, KRESHOCK A R. Propeller whirl flutter stability and its influence on X-57 aircraft design[J]. Journal of Aircraft, 2018, 55(5): 2169-2175.
[8] KIM H D, PERRY A T, ANSELL P J. A review of distributed electric propulsion concepts for air vehicle technology: AIAA-2018-4998[R]. Reston: AIAA, 2018.
[9] WANG S, ECONOMOU J T, TSOURDOS A. Indirect engine sizing via distributed hybrid-electric unmanned aerial vehicle state-of-charge-based parametrisation criteria[J]. Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering, 2019, 233(14): 5360-5368.
[10] KERHO M F. Aero-propulsive coupling of an embedded, distributed propulsion system: AIAA-2015-3162[R]. Reston: AIAA, 2015.
[11] KERHO M, KRAMER B. Turboelectric distributed propulsion test bed aircraft: NNX14AF44A[R]. El Segundo: Rolling Hills Research Corporation, 2013.
[12] PIEPER K, PERRY A, ANSELL P, et al. Design and development of a dynamically, scaled distributed electric propulsion aircraft testbed[C]//2018 AIAA/IEEE Electric Aircraft Technologies Symposium. Piscataway: IEEE Press, 2018: 1-2.
[13] BORER N K, DERLAGA J M, DEERE K A, et al. Comparison of aero-propulsive performance predictions for distributed propulsion configurations[C]//55th AIAA Aerospace Sciences Meeting. Reston: AIAA, 2017.
[14] SCHETZ J A, HOSDER S, DIPPOLD V III, et al. Propulsion and aerodynamic performance evaluation of jet-wing distributed propulsion[J]. Aerospace Science and Technology, 2010, 14(1): 1-10.
[15] LEIFSSON L, KO A, MASON W H, et al. Multidisciplinary design optimization of blended-wing-body transport aircraft with distributed propulsion[J]. Aerospace Science and Technology, 2013, 25(1): 16-28.
[16] MA Y Y, ZHANG W, ZHANG Y Z, et al. Effects of distributed propulsion crucial variables on aerodynamic and propulsive performance of small UAV[C]//Proceedings of the 2018 Asia-Pacific International Symposium on Aerospace Technology (APISAT 2018), 2019: 1535-1550.
[17] YOO S, DUENSING J. Computational analysis of the external aerodynamics of the unpowered X-57 mod-III aircraft: AIAA-2019-3698[R]. Reston: AIAA, 2019.
[18] DEERE K A, VIKEN S, CARTER M, et al. Computational analysis of powered lift augmentation for the LEAPTech distributed electric propulsion wing: AIAA-2017-3921[R]. Reston: AIAA, 2017.
[19] DEERE K A, VIKEN J K, VIKEN S, et al. Computational analysis of a wing designed for the X-57 distributed electric propulsion aircraft: AIAA-2017-3923[R]. Reston: AIAA, 2017.
[20] 贾毅, 张永升, 刘丹, 等. 无人机气动力地面车载测试系统[J]. 实验流体力学, 2013, 27(3): 81-86. JIA Y, ZHANG Y S, LIU D, et al. A ground test vehicle(GTV)system to measure the aerodynamic characteristics of unmanned air vehicles[J]. Journal of Experiments in Fluid Mechanics, 2013, 27(3): 81-86 (in Chinese).
[21] DUBOIS A, VAN DER GEEST M, BEVIRT J, et al. Design of an electric propulsion system for SCEPTOR’s outboard nacelle: AIAA-2016-3925[R]. Reston: AIAA, 2016.
CJA