Effect of local increase of elements order on the accuracy of solution of stationary geoelectric problems

Problem of accuracy increase by local increase of order of finite elements is considered for the task of calculation of stationary electric field. The following three dimensional geoelectric problem is solved: 3D object is embedded in some media, grounded electric line is electric field source. Method of field part selection is used for solving. T-transform technique is used for matching finite elements of different orders. Three different basises were used with different placement of higher order finite elements. Obtained solutions were compared with solutions obtained on nested grids.