Method for generating tetrahedron gridding for three-dimensional geological structure

Abstract

The invention discloses a method for generating a tetrahedron gridding for a three-dimensional geological structure, which is used for geologic body attribute modeling and oil-deposit numerical simulation computation and analysis. The invention is characterized in that an automatic reliable recovering method for geologic restrained boundary segments and layering gridding is supplied and the tetrahedron gridding under the restraining of inputting a three-dimensional geological structured model is generated, on the basis of a standardized settling for inputting a three-dimensional geological surface gridding model and the Delaunay triangulation gridding generating method based on a point set, and by utilizing a topologic principle and detecting constraint conditions and crossing conditions of the elements such as edges, sides and bodies in an antithetical Voronoi diagram of a Delaunay tetrahedron gridding as well as establishing a corresponding point adding rule. The method is easily realized, has high reliability and has no specific demand on complexity of an initial surface model and the classification of the gridding. By using the method, the problem of gridding the tetrahedron under a complex geological structure is solved, thereby being convenient to perform further analysis and simulation computation on the three-dimensional geological model on such a basis.

Description

technical field [0001] The present invention relates to the fields of computational geometry, computer graphics, mathematical geology, three-dimensional geological modeling, and reservoir numerical simulation and calculation. Next, generate tetrahedral cells that fill the entire 3D geological target area without overlap, without holes, and without passing through any 3D geological layer structure. It specifically involves level constraint processing, constraint line segment recovery and constraint surface recovery, element size control and optimization, etc. Background technique [0002] The 3D geological model is an important tool used to describe the three-dimensional geological spatial form, describe the distribution of geological attributes, perform three-dimensional expression, display and geological analysis. At present, most of the three-dimensional geological models describe their structure based on the geometric reconstruction of layers, while the geological body A...

AI Technical Summary

Problems solved by technology

[0005] The problem of generating tetrahedral meshes under the condition of existing constraint levels is generally called the problem of constrained tetrahedral mesh generation. At present, some research results have achieved certain results for engineering application problems, but these methods are more for individual In practical engineering applications, the results of the algorithm are not guaranteed, and it cannot be applied to the generation of tetrahedral meshes in general three-dimensional complex geological structures

In addition, this problem has also been systematically studied theoretically by some scholars from the perspective of computational geometry, and theoretically gave a generation algorithm for Delaunay tetrahedral meshes under any limited conditions, but these research results pay more attention to theoretical In terms of the complete solution performance of this problem, the given algorithm has strict requirements on the geometric norm of the input conditions, so it is difficult to apply to 3D geological structures with strong non-manifold and complex free-form surface characteristics The above results, and these algorithms still have certain problems in terms of realizability and robustness.

Images