A new topography adapted mesh generation process tailored to simulate Atmospheric Boundary Layer (ABL) flows on complex terrains is presented. The mesher is fully automatic given: the maximum and minimum surface mesh size, the size of the first element of the boundary layer, the maximum size in the boundary layer and the size at the top of the domain. The following contributions to the meshing workflow for ABL flow simulation are performed. First, we present a smooth topography modeling to query first and second order geometry derivatives. Second, we propose a new adaptive meshing procedure to discretize the topography based on two different metrics. Third, the ABL mesher is presented, featuring both prisms and tetrahedra. We extrude the triangles of the adapted surface mesh, generating prisms that reproduce the Surface Boundary Layer. Then, the rest of the domain is meshed with an unstructured tetrahedral mesh. In addition, for both the surface and volume meshers we detail a hybrid quality optimization approach, analyzing its impact on the solver for high-complexity terrains. We analyze the convergence of the triangle adaptive approach, obtaining quadratic convergence to the geometry and reducing to one half the error for the same amount of degrees of freedom than without adaptivity and optimization. We also study the mesh convergence of our RANS solver, obtaining quadratic mesh convergence to the solution, and using a 30% of the degrees of freedom while reducing a 20% of the error of standard semi-structured approaches. Finally, we present the generated meshes and the simulation results for a complete complex topographic scenario.
翻译:为模拟大气边界层(ABL)在复杂地形上的流动而专门设计的新的地形调整后网格生成过程。 介质是完全自动的: 最大和最小表面网格尺寸、 边界层第一个元素的大小、 边界层的最大尺寸以及域顶部的大小。 以下对ABL流模拟的网格流程的贡献被执行。 首先, 我们为查询第一和第二顺序的几何衍生物( ABL) 提供了平滑的地形模型模型模型。 其次, 我们提出一个新的适应性网格方法, 将基于两种不同度的地形分解。 第三, 展示了ABL mesher, 包括棱镜和四肢层的表面网格尺寸。 我们扩展了经调整后的表面网格网格网格的三角形, 复制了地表边界图图图图图图图层的精度。 然后, 将区域域的其余部分与一个不结构的四面板模模模模模模模模模。 此外, 我们详细介绍了一种混合质量优化方法, 分析其对高度和体积面面面面面面面的分辨率的分辨率的影响,, 分析其对于高度的分辨率的分辨率的深度的深度的深度的深度分析其影响,,, 将我们用一个方向的平整为一个方向的平整, 将一个方向的平整法, 我们分析一个方向的平整, 将一个方向的平整到一个方向的平整到一个方向, 。