Aerodynamic shape optimization framework for engine installation in an unconventional airframe

用于非常规机身中发动机安装的空气动力学形状优化框架

• 批准号: RGPIN-2022-03586
• 负责人: Germain, Patrick
• 金额: $ 2.04万
• 依托单位: École de technologie supérieure
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=754441
• 关键词: Aerodynamic; shape; optimization; framework; engine

The major challenge for the transport aircraft industry in the next 20-30 years is the reduction of its carbon dioxide emissions in operation. The development of technologies to increase the energy efficiency of the aircraft must continue in parallel with the efforts to switch the source of energy from fossil fuel to a carbon-free source, such as hydrogen or electricity. The contribution to the jump in efficiency from the change of aircraft configuration alone could be large, up to 30% in the case of the blended-wing body (BWB) through drag reduction. Such revolutionary development however represents an important financial and technological risk, until its associated technology roadblocks are removed. One of these roadblocks is that even though modern engines also improve from generation to generation, their operability and high efficiency remain susceptible to the quality of the flow at the face of the engine or the fan. As the fan blades rotate through successive pockets of changing flow properties, too much spatial gradients from pocket to pocket can lead to issues of stability and structural integrity for the engines. This problem is exacerbated by unconventional configurations, such as the flying wing or the BWB, particularly when the engines are integrated (buried) in the airframe. It is thus important to elevate the maturity of these unconventional configurations to reduce the technological risk. If the flow behavior is not examined early in the design phase and sufficiently stabilized, there is the high risk that the aircraft configuration becomes impractical and that the efficiency gain above is neither protected nor realized. It is proposed to elaborate aircraft configurations with highly integrated propulsion systems beyond the conceptual level, achieving low drag (high efficiency) and taking advantage of passive flow control to maintain adequate flow uniformity at the engine(s) with demanding spatial requirements. With examples of unconventional configurations in the available literature, it is proposed to review, explore and determine aerodynamic shapes for their inlet (S-duct) and the portions of their external surfaces that are affected by the installation of the engine(s), such that these will operate satisfactorily at any flight conditions, thereby removing the technological roadblock associated with propulsion/airframe integration (PAI). Multiple constraints that are representative of the realistic aircraft operating envelope will be considered. A virtual aerodynamics laboratory or test bed will be created through the construction of a design framework for automatic shape optimization. For example, the impact of aero-shaping of the airframe and the inlet will be quantified. The efficiency of a powerplant installed in nacelles on pylon will be compared accurately with that embedded in the airframe.

未来20-30年运输机行业面临的主要挑战是减少运营中的二氧化碳排放。在开发提高飞机能源效率的技术的同时，必须继续努力将能源从化石燃料转换为无碳来源，如氢气或电力。单是飞机外形的改变对效率的提高的贡献可能是很大的，对于通过减阻的混合翼身(BWB)来说，贡献高达30%。然而，在消除与之相关的技术障碍之前，这种革命性的发展会带来重大的金融和技术风险。其中一个障碍是，尽管现代发动机也在一代又一代地改进，但它们的可操作性和高效率仍然受到发动机或风扇表面流动质量的影响。当风扇叶片在不断变化的流动特性的连续凹槽中旋转时，从凹槽到凹槽的太多空间梯度可能会导致发动机的稳定性和结构完整性问题。飞翼或BWB等非传统配置加剧了这一问题，特别是当发动机集成(埋在)机身中时。因此，重要的是提高这些非常规配置的成熟度，以降低技术风险。如果在设计阶段没有及早对流动行为进行检查并充分稳定，则飞机外形变得不切实际的风险很高，上述效率收益既不受保护也不能实现。建议采用概念层面以外的高度集成推进系统的飞机配置，实现低阻力(高效率)，并利用被动流动控制来保持发动机足够的流动均匀(S饰)，并对空间要求苛刻。以现有文献中的非常规构型为例，建议审查、探索和确定其进气道(S导管)及其外表面受发动机安装(S)影响的部分的气动形状，使其在任何飞行条件下都能令人满意地运行，从而消除与推进/机身一体化相关的技术障碍。将考虑代表现实飞机运行包络的多个约束。将通过构建自动形状优化的设计框架来创建虚拟空气动力学实验室或试验台。例如，机身和进气口气动成形的影响将被量化。安装在塔架机舱中的动力装置的效率将与安装在机身中的动力装置的效率进行准确的比较。