Computational methods for high-Reynolds number viscous flows around complex configurations.

计算流体力学(CFD)在过去的30年里经历了非凡的发展。现在CFD领域的最先进技术已经发展到能够通过求解Euler和Reynolds平均的Navier-Stokes方程来评估复杂、完整的飞机外形的流动。然而，对三维物体高雷诺数流动的模拟还远远不能用于常规设计工作的实际应用。真正的瓶颈之一是围绕复杂配置生成适当网格的过程非常耗时。为了避免这种情况，S从80年代中期开始加快了非结构网格方法的发展，因为非结构网格方法具有很好的处理复杂结构的能力。然而，即使有了这些快速的改进，非结构化网格方法仍然不能达到相对于结构化网格方法的优势。这主要是因为与现有的结构化网格方法相比，非结构化网格方法的效率很低。在本研究中，提出了一种使用棱柱网格的新方法来计算航空应用复杂外形周围的高雷诺数粘性流场。它包括棱柱体网格生成方法和有限体积流动求解器。将该方法应用于波音747飞机模型周围的流动计算，验证了该方法的有效性。柱面网格方法是求解外部粘性流动问题的一种结构网格方法和非结构网格方法之间的折衷方法。目前正在进行工作，以处理更复杂的配置，包括内部流动问题。为此，边界层区域的棱柱体网格和剩余区域的四面体网格的组合是一种非常有前途的方法。

The computational fluid dynamics (CFD) has undergone an exceptional growth in the last 30 years. Now the state of the art in the area of CFD has evolved to the ability to evaluate the flow about complex, complete aircraft configurations by solving Euler and Reynolds-averaged Navier-Stokes equations. However simulations of the high Reynolds number flow about a three-dimensional body are still far from the practical use for the routine design works. One of the real bottlenecks is the time-consuming procedure to generate an appropriate grid around a complex configuration. The development of the suitable meshing schemes is still an ongoing process, especially for three-dimensional viscous flow simulations.To circumvent this situation, a development of unstructured grid methods has been accelerated from mid 80's because of their attractive capabilities for complex configurations. However, even with these rapid improvements, the unstructured grid methods cannot attain superiority over the structured grid methods yet. This is mainly because of the painful inefficiency of the unstructured grid methods when compared to available structured grid methods.In this research, a new method using a prismatic grid has been developed to compute high-Reynolds number viscous flow fields around complex configurations of aeronautical applications. It includes a prismatic grid generation method and the finite volume flow solvers. The capability of the method was demonstrated by applying it for flow computations around Boeing 747 airplane models.The prismatic grid approach is a practical compromise between structured and unstructured grid approaches for external viscous flow problems. Work is now underway to treat more complex configurations including internal flow problems. For this purpose, a combination of the prismatic grid for the boundary layr regions and the tetrahedral grid for the remaining region is a very promising approach.