Using of partly-boundary elements as a version of the indirect near-boundary element method for potential field modeling

In this paper, the partly-boundary elements as a version of the indirect near-boundary element method has been considered.  Accuracy and effectiveness of their using for 2D problems of potential theory have been investigated.  It is shown that using of partly-boundary elements for objects of canonical shape (circle, square, rectangle, ellipse) and arbitrary polygons allows us to achieve the solution accuracy, which is comparable with the accuracy of the indirect near-boundary element method, and its order of magnitude is higher than in the indirect boundary element method.  In this case, the computation time is reduced by 2–2.5 times than in the near-boundary element method case.  The software of the proposed approach has been implemented in Python.  Practical testing was carried out for the tasks of electrical profiling and vertical electrical sounding in the half-plane with inclusion as a polygon.  The recommendations for application of the partly-boundary elements in geophysical practice have been given.

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