Simulations of icing and transitional flows using RANS modeling around 3D full aircraft configurations

航空运输业正在引入越来越严格的认证要求（例如在结冰条件下飞行）和/或性能增强目标（减少二氧化碳）。 该项目在航空结冰和过渡流领域为复杂的3D飞机几何形状开发新的空气动力学模型，可供飞机制造商用于实现其设计目标。环境条件可能导致飞机表面结冰，导致性能下降，从而影响安全性。 特别是在结冰大气条件下飞行时，必须确定过冷大液滴对飞机高升力空气动力学的影响。 同时，高速层流机翼被认为是减少飞机阻力的一种可能的手段，但是后掠机翼上的三维流动可以触发在二维机翼上不明显的物理机制（例如，从层流到湍流状态的横流过渡）。 转捩在将高升力（层流气泡）和高速（激波）流的风洞试验结果外推到飞行状态方面起着重要的作用。 因此，该研究项目建议开发一个航空结冰套件，特别注意在复杂的现实高升力几何形状和3D过渡湍流模型上进行强大的3D模拟。 最后，通过非线性涡格方法的低保真度模型将用于在结冰安全裕度和燃料减少增益之间进行权衡。结冰条件下复杂几何形状的增升装置（缝翼或襟翼）的几何复杂性通过使用非结构化网格技术来处理，而高速流将使用与结构化网格上的新型三维网格生成技术相结合的Chimera方法来解决。该项目将在这些领域培训HQP，以及高性能计算和源代码开发。 最终的交付成果将使赞助商庞巴迪宇航公司和整个加拿大社区受益，因为航空结冰和过渡流对许多部门都有影响，如风能、电力运输等。**

The air transport industry is introducing more and more stringent certification requirements (such as flight into icing conditions) and/or performance enhancement targets (CO2 reductions). This project develops new aerodynamic models in the areas of aero-icing and transitional flows for complex 3D aircraft geometries that can be used by aircraft manufacturers to achieve their design goals.**Environmental conditions can lead to formation of ice on the aircraft surfaces, leading to reduced performance that can affect security. Notably during flight into icing atmospheric conditions, the effects of Supercooled Large Droplets on the aircraft's high-lift aerodynamics must be determined. Simultaneously, high-speed laminar flow wings are seen as a possible means of reducing aircraft drag, but three-dimensional flow over swept wings can trigger physical mechanisms that are not apparent in their 2D counterparts (e.g. cross-flow transition from laminar to turbulent regimes). Transition plays an important role in extrapolating wing-tunnel results on high-lift (laminar bubbles) and high-speed (shock waves) flows to flight conditions. The research project thus proposes to develop an aero-icing suite with special care in robust 3D simulations over complex realistic high-lift geometries and 3D transitional turbulence models. Finally, low-fidelity models via a non-linear Vortex Lattice Method will be used to perform trade-offs between icing security margins and fuel reduction gains. Geometrical complexities of high-lift devices (slats or flaps) over complex geometries in icing conditions are treated via the use of unstructured grid techniques, whereas high-speed flows will be solved using the Chimera approach coupled to novel 3D mesh generation techniques on structured grids. This project will train HQP in these areas, as well as high performance computing and source code developments. The final deliverables will benefit the sponsor, Bombardier Aerospace, and the entire Canadian community as aero-icing and transitional flows have impacts on many sectors i.e. wind energy, transport of electricity, etc. **************************