An algorithm for rapid ground surface mesh generation used in complex terrain wind field simulation

Abstract

In the study of wind engineering problems, it is of considerable importance to obtain accurate surface wind field characteristics. Surface features have significant impacts on the characteristics of small- and micro-scale wind field, so the fine reconstruction of terrain features is the basis of small- and micro-scale wind field simulations. However, since the GIS data obtained by satellite scanning cannot be directly used for CFD numerical simulation, the geographic information data is usually of considerable amount and contains a large number of waste points, thus difficult to be completed by manual modeling. To solve this problem, an automatic waste point repair algorithm and a grid aggregation method based on greedy algorithm are proposed, which can quickly and efficiently reconstruct the surface and generate the grid. Relying on the national numerical wind tunnel project and integrating the above core algorithms with the pre-processing and post-processing modules, a general and efficient surface mesh generation software ESM (Earth Surface Mesh) has been developed. Compared with the surface modeling and grid generation modules provided by other software, ESM has more comprehensive functions, and surface grid rapid generation technologies such as waste point data processing, grid adaptive refinement based on elevation change, high fidelity interpolation technology and partition splicing generation. It supports more interfaces and can generate structured and unstructured grids. The preliminary example shows that the surface grid generated by ESM meets the needs of wind engineering simulation.