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.

运输飞机行业未来20-30年的主要挑战是减少运营中的二氧化碳排放。提高飞机能源效率的技术开发必须与将能源从化石燃料转换为无碳能源（例如氢或电）的努力同时进行。仅改变飞机构型对效率提升的贡献就可能很大，在混合翼机身 (BWB) 的情况下，通过减阻，效率提升的贡献可能高达 30%。然而，在相关技术障碍被消除之前，这种革命性的发展代表着重要的财务和技术风险。这些障碍之一是，尽管现代发动机也一代又一代地改进，但它们的可操作性和高效率仍然容易受到发动机或风扇表面的流动质量的影响。当风扇叶片旋转通过连续变化的流动特性的凹穴时，凹穴与凹穴之间太大的空间梯度可能会导致发动机的稳定性和结构完整性问题。非常规配置（例如飞翼或 BWB）会加剧这个问题，特别是当发动机集成（埋藏）在机身中时。因此，提高这些非常规配置的成熟度以降低技术风险非常重要。如果没有在设计阶段的早期检查流动行为并使其足够稳定，那么飞机配置就很可能变得不切实际，并且上述效率增益既得不到保护也得不到实现。建议在概念层面上精心设计具有高度集成推进系统的飞机配置，实现低阻力（高效率）并利用被动流量控制来在具有严格空间要求的发动机上保持足够的流量均匀性。通过现有文献中非常规配置的示例，建议审查、探索和确定其入口（S 管道）的空气动力学形状以及受发动机安装影响的外表面部分，例如这些将在任何飞行条件下令人满意地运行，从而消除与推进/机身集成（PAI）相关的技术障碍。将考虑代表实际飞机运行范围的多个约束。通过构建自动形状优化的设计框架，创建虚拟空气动力学实验室或测试台。例如，机身和进气道的气动造型的影响将被量化。安装在塔架短舱中的动力装置的效率将与嵌入机身中的动力装置的效率进行准确比较。