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Specific Absorption Rate Computations with a Nodal-Based Finite Element Formulation

By Ruben Otin and Herve Gromat
Progress In Electromagnetics Research, Vol. 128, 399-418, 2012


The aim of this work is to asses the performance of a nodal-based finite element formulation when applied to the computation of specific absorption rate (SAR) problems. This formulation solves numerically the regularized Maxwell equations using nodal elements and, in principle, it offers several advantages: It provides spurious-free solutions and well-conditioned matrices without the need of Lagrange multipliers or scalar potentials. Its integral representation is well-suited for hybridization with integral numerical techniques because of a low-order singular kernel. Also, the nodal approximation of the electromagnetic problem is easier to couple to a thermal finite element problem which usually also employs nodal elements. But, on the other hand, we need to take special care of the points of the domain where the field is singular to obtain accurate solutions. In this paper, we show the impact of the singularities on the performance of the proposed finite element formulation and how its good features are affected when solving real-life SAR problems.1


Ruben Otin and Herve Gromat, "Specific Absorption Rate Computations with a Nodal-Based Finite Element Formulation," Progress In Electromagnetics Research, Vol. 128, 399-418, 2012.


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