We present here an original application linking an electrochemical domain and the computational aspect of electromagnetic fields to make a corrosion diagnosis of a protected underwater steel structure. After a defined operating time, it is mandatory to check an underwater steel structure. This control may happen too early, if the protection has not been damaged; but it may happen too late, if some particularly bad environmental conditions have already damaged the structure. Moreover, current examination techniques require immobilizing the structure for a long time: they may be complicated to dry (pipe lines or tanks) or to place in dry docks for vessels. The efficiency of these techniques could be improved. The purpose of this paper is to replace this checking/examination by a series of close electrical measurements in the electrolyte which provides a corrosion diagnosis of the structure. This also allows computing the electric and magnetic fields caused by this phenomenon everywhere in the electrolyte. The new method introduced ensures a great time-saving but also an accuracy never reached before.

Following ICNIRP Guidelines of 1998, European Parliament in 2004 has stated the reference levels for workers exposure to electromagnetic fields. In low frequency regime, due to the nature of the basic mechanism of short term interaction, the exposure limits are based on the values of induced eddy currents inside human body, thus electromagnetic simulation is an important tool for the assessment of electromagnetic field exposure. This paper presents a method for computing eddy currents inside human body and applies the method to the evaluation of eddy currents induced by a resistance spot welding system. A comparison between results obtained with two different models of human body and with different discretization levels is performed and results are discussed.