The time domain finite element algorithm has been widely used in airborne electromagnetic three-dimensional forward modeling. However, due to the large airborne electromagnetic measurement area and dense sampling, the forward calculation is huge, and the traditional serial algorithm cannot meet the calculation efficiency requirements. In view of such a situation, the authors carried out parallel acceleration algorithm research to solve the problem of insufficient computational efficiency. Based on the limited range of influence of aviation electromagnetic system, the local grid technology is used to divide the computing task into multiple sub-grids, that is, a set of grids for each source, and the forward calculations of each grid are independent of each other, and hence no data dependency is existent and there is good parallelism. In this paper, MPI technology is used to allocate multiple sub-grid forward tasks, and parallel computing is performed on each process. For each forward subgrid, in the forward modeling of the time domain finite element algorithm, the parallel matrix is calculated by OpenMP technology. The numerical simulation results of the typical electrical model show that the MPI+OpenMP parallel forward algorithm developed in this paper can effectively improve the forward speed, and the maximum acceleration ratio can reach 10 times.
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