基于全乘波压缩面的背部进气高超飞行器构型探究

Basic requirements of next-generation hypersonic cruise vehicles include high lift-to-drag ratio and large effective volume. Besides, such aircrafts always flight at small angle of attack. To aim at these requirements and characteristics, a conceptual configuration based on multi-waveriders- combination with dorsal mounted engines is proposed in this application. The basic idea is as follows. Two scramjets are mounted on the top of a waverider, and the pre-compression surface of each inlet of scramjet is also designed as a waverider. Therefore, advantages of waveriders include high lift-to-drag ratio, high airflow mass catch, and uniform compression are fully retained. Compared with present configurations with abdominal intake, higher aerodynamic performance may be obtained since the disturbance to the lower surface of the vehicle derived from scramjet modules was eliminated. In addition, such a configuration leads to more reasonable use of the volume. .The target of this project is to explore a new way of configuration design for long-range hypersonic aircrafts. Correspondingly, various modules included parameterized design methods of complex surfaces, computational fluid dynamics, nonlinear optimization methods will be integrated as essential tools; and a series of studies of configurations design, performances evaluation, and aerodynamic shapes optimization will be carried on. We deem that a family of advance configurations with promising perspective will be developed at the end of the project. Moreover, expected results also include performances parameters of these configurations and primary rules between these parameters and corresponding design variables. We also have faith that these results will directly support the configuration development of next-generation hypersonic near-space aircrafts.

针对下一代高超声速巡航飞行器高升阻比、大有效容积等设计需求及小攻角巡航的特点，提出一种基于多乘波体组合的背部进气布局飞行器概念，旨在为长航时高超声速飞行器构型设计探索一条新途径。主要思路为以完整的乘波体作为飞行器下表面，其背部搭载两台发动机，且每个流道的进气道外压缩面亦采用垂直布置的乘波体。该方案将同时利用乘波体高升阻比、高来流捕获量及压缩均匀等优势，且由于去除了发动机对机体下表面的干扰，较腹部/旁侧进气布局应可获得更好的气动性能，并可更加有效的利用容积。具体研究拟结合运用复杂曲面参数化方法、计算流体力学及非线性数值优化方法等工具，依次开展构型设计、性能评估及气动优化等工作。预期可提出一类具有工程推广前景的先进构型，获得其相关的气动/几何性能参数，并总结出相关设计参数对上述性能影响的初步规律，从而为下一代高超声速飞机的构型设计提供直接支撑和有价值的参考。

高超声速飞机是目前国内外的热点研究对象。依据进气方式可主要分为腹部进气、旁侧进气和背部进气三种布局。本项目以提升整机宽速域气动性能为主要目标，基于背部进气布局开展了一系列探索性研究。旨在为长航时高超声速飞行器构型设计提供一条新思路。主要工作包括：.1）发展了一种组合前缘乘波体设计方法。结果表明运用该方法生成的乘波体可在较大参数范围内获得较好的升阻比，且外形相对平坦的乘波体构型其升阻比较优。以此为基础，发展了一种三乘波体前体的生成方式。并进一步开展了初步的翼身融合整机设计。分析结果表明，在考虑粘性的情况下，构型下表面均保持较完整的乘波特性，从而有效提升整机气动性能，并可实现纵向静稳定。.2）开展了背置单进气口布局的构型研究。计算结果表明前体对来流质量流量具有较好的捕获能力，于设计工况基本实现激波封口，出口马赫数分布均匀，受攻角、侧滑角的影响较小。另外，此类构型较易实现纵向和航向的静稳定性设计，利用乘波体的自然外凸亦可实现横向静稳定。.3）以升阻比最大作为优化目标，基于背置单进气口布局构型，结合运用CFD分析、均匀实验设计方法、代理模型方法和遗传算法开展了气动外形优化设计。结果表明，其最优升阻比于2°飞行攻角条件下可达6.55。此外还开展了多攻角、侧滑角工况的气动性能评估。.4）结合一种典型的TBCC发动机模块，以未来高超声速客机为应用设想，开展了具有实用化前景的飞行器概念研究。结果表明，即便在考虑发动机内流道阻力的条件下，采用背置单进气口布局的构型仍可获得较高的升阻比。同时，通过压缩面形状变化，可有效改善内部容积。另外，压缩面形状变化还对整机压心位置有较为明显的影响，因此也可作为飞行器配平姿态调整的有效手段。.研究结果表明，由于飞行器下压缩面可以采用完整的乘波体设计，因此其在高超声速巡航条件下升阻比可以有效提升并满足发动机来流要求，可作为未来高超飞机的备选方案。