Sensitivity Matrix of an ECT System by Using FEA

An electrical capacitance tomography (ECT) system is analyzed by a 2D finite element method (FEM). Special focus is given to the sensitivity matrix evaluation in order to avoid the inherent numerical errors originated by the capacitance computation and by using the difference approximations for the Jacobian matrix. The FEM is applied to obtain the electric field. A new approach for the sensitivity matrix is developed by calculating capacitances and the Jacobian matrix using the FEM formulation itself. Comparisons with published works are done.