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空天飞行器飞行速域宽,气动外形需同时考虑起飞高升力与超/高超声速高升阻比需求,给飞行器的气动布局设计带来很大难度。双向飞翼飞行器概念具有两个互相垂直的对称面,在亚声速时以大展弦比模态飞行,可获得足够的升力,超/高超声速时以小展弦比模态飞行,可尽量降低激波阻力,飞行模态转换的转换通过机身旋转90°实现,可能解决宽速域高升阻比设计矛盾。本文据此构建了一种双向飞行空天飞行器外形,并开展了CFD数值仿真。结果表明,与Sanger类常规布局的空天飞行器相比,双向飞翼概念外形的亚声速时最大升阻比为16,提升30%~50%;高超声速段升阻比性能基本相当,最大升阻比4,说明该外形是一种有潜力的空天往返飞行器方案。在此基础上,从飞行器技术实现角度,系统梳理了双向飞翼飞行器方案面临的三大技术难点,并提出了可行的解决途径或可能的攻关方向。针对飞行器纵向静不稳定度偏大问题,提出调整机身平面形状和剖面形状等,可使静不稳定度降低至10%以内;针对飞行模态转换控制困难问题,创新性地提出了一种基于非对称垂尾的控制方法,在飞行器两个飞行模态下各安置一片垂尾,在提供了足够的模态转换控制力矩的同时,改善了飞行器的横航向稳定性;针对发动机耦合设计问题,提出了一种新的涡轮和火箭发动机独立垂直布置的方法,降低了空天飞行器对组合动力技术的依赖性,有助于双向飞翼空天飞行器的早日实现。
Airspeed wide range of flight speed, aerodynamic shape at the same time take into account the high take-off and supersonic / hypersensitivity demand ratio, the aerodynamic layout of the aircraft to bring great difficulty. The two-way flying wing concept has two planes of symmetry perpendicular to each other, with a large aspect ratio mode of flight at sub-sonic speeds, sufficient lift is achieved, with super-high / supersonic modes flying at a small aspect ratio, minimizing Shock resistance, flight mode conversion conversion through the fuselage rotated 90 ° to achieve, may solve the wide-area high resistance ratio design conflicts. Based on this, a kind of bi-directional flying aero spacecraft is constructed and CFD numerical simulation is carried out. The results show that compared with the spacecraft of the Sanger class, the maximum drag-and-drag ratio of the two-way flying wing is 16 at subsonic speeds, increasing by 30% -50% Resistance ratio 4, indicating that the shape is a promising space shuttle program. On this basis, from the point of view of aircraft technology, systematically combing the three technical difficulties faced by the two-way flying-wing aircraft program and put forward feasible solutions or possible direction of tackling the problem. Aiming at the large longitudinal instability of aircraft, it is proposed to adjust the plane shape and cross-sectional shape of the fuselage so as to reduce the static instability to less than 10%. Aiming at the difficulty of flight mode transition control, Based on the control method of asymmetric vertical tail, a vertical tail is placed in each flight mode of the aircraft, which provides sufficient modal conversion control torque and improves the stability of the aircraft in the transverse direction. In view of the problem of engine coupling design , A new independent vertical arrangement of turbo and rocket engines is proposed, which reduces the dependency of spacecraft on combined power technology and contributes to the early realization of bi-directional flying-wing airship.