Formulations for Numerical Dosimetry of Currents Induced in the Human Body by ELF Magnetic Fields
Résumé
The fields induced in the human body by ELF electromagnetic fields are extremely weak, and hence very difficult to measure; therefore numerical dosimetry is an important issue. The most used formulation of magnetically induced fields is the phi-a formulation, which takes benefit of the particular features of the human body [1,2] : the displacement currents and the reaction field may be neglected for low frequencies (less than 1 MHz). However, this formulation requires as source term a magnetic vector potential, which is difficult to obtain from measurements of the magnetic field. This requirement can be a problem in practical situations where an accurate model of the radiating source is not available. In this work, we propose a new t-b formulation for ELF numerical dosimetry which, under the same assumptions of phi-a formulation, allows to compute the induced fields by taking as source term directly b. As in the phi-a formulation, the computation domain is bounded to the human body.