Study Of 3D Stratum Modelling And Visualization Method Based On MPI

3D stratum modeling and visualization technique is one of focus and hot issues in the field of 3D stratum simulation research. Through 3D stratum visualization image geological and morphological structure, can enhance the accuracy and intuitive stratum analysis, thus reduce the huge risk of underground engineering design and construction. However the amount of data increases in the visual rendering process, the computational and rendering time is too long, so we adopt parallel architecture of large-scale dealing with stratum data processing and can rapidly finish complex stratum modeling, enhance rendering visualization speed.Based on the study of parallel computing and methods of 3D stratum visualization, using data parallel partition visualization, using standard message transfer interface(MPI) and fourth generation visual language IDL. That is, MPI completes data parallel communication, IDL completes drawing process. MPI implementations call the IDL in a shared library functions and data structure interface, operating IDL underlying data and functions directly. The key issues solved include the following two aspects:1. Researching 3D stratum modeling method, using borehole data, using multi-DEM simulation of multi-surface model stratum and the different strata DEM data organization, the use of hierarchical management, taking into account the level of interpolation fit may be due to pinch-out stratigraphic point of intersection appears Phenomenon, the sampling point detection method to determine the point boundary curve belongs to the location of formation. DEM modeling is based on the multi-layer, the surface level as the sub-strata space, ground situation display in order to distinguish, for the same kind of body to give the same kind of formation property values.2. Parallel visualization solution by drawing the process of visualization and mapping the computational problem of long time to improve the visual rendering speed. To achieve the comprehensive comparison of parallel computation based on the method, using data parallel approach, the use of MPI in more than one PC, LAN Windows XP system to build a parallel computing environment, the use of master-slave mode, complete the distribution and reception of data, faster Completion of the drilling data Kriging process. MPI calls using IDL data and function interfaces available to achieve visualization of three-dimensional formation.To test the parallel effect of parallel computing based on the built environment, in different number grids and nodes separately process interpolation efficiency test, and the results showed that the through after MPI parallel computing indeed speed obviously improved and in a large computing scale,effect is more obvious. But by the communication time and other factors, in the same calculation scale, with the increase of computing node, parallel computing is not high on the use of computer resources, leading to parallel efficiency decreased.