Nathan IDA
Professor, Department of Electrical and Computer Engineering, The University of Akron, USA
Research interests:
Computational Electromagnetics, Nondestructive Evaluation of Materials, Wave Propagation in Materials, Scattering, Antennas, Electromagnetic Compatibility, Computer Algorithms and Computer Methods.
Keynote address:
AC Induced Corrosion - Low and High Frequency Effects
Abstract:
As a rule, corrosion is viewed as an electrochemical process based on DC cells. The process of
cathodic protection itself, is that of countering the flow of charges with opposing polarity cells or sources, either active or passive. As a result, the possibility of AC induced corrosion has been excluded until relatively recently. However, following multiple anecdotal incidents of corrosion in gas and oil pipelines in right-of-way corridors, it became apparent that additional effects are at work and a recognition that power frequency induced current can and do cause corrosion or, at the very least contribute to it. In fact, some well documented cases have shown that AC induced corrosion can be more aggressive and can corrode through pipelined in record times. Later, additional evidence of corrosion due to high frequency electromagnetic radiation on navy ships due to exposure to radar has come to the forth.
Current models attempting to explain these effects rely on surface potentials with the addition of rectifying effects in the anodic and cathodic branches as well as the conventional DC elements. Our work was initially based on experiments followed by simulation and finally lead to a proposed mechanism of rectification. Simulation has shown, as expected, that any nonlinearity in the current path can lead to a net DC level. The model for rectification is based on two possible mechanisms. One is the well-known electrolytic rectification mechanism. The second is based on the Schottky metal-semiconductor interface with corrosion products forming the semiconductor. Both of these mechanisms help explain the low and high frequency corrosion effects from a macroscopic point of view.
Current models attempting to explain these effects rely on surface potentials with the addition of rectifying effects in the anodic and cathodic branches as well as the conventional DC elements. Our work was initially based on experiments followed by simulation and finally lead to a proposed mechanism of rectification. Simulation has shown, as expected, that any nonlinearity in the current path can lead to a net DC level. The model for rectification is based on two possible mechanisms. One is the well-known electrolytic rectification mechanism. The second is based on the Schottky metal-semiconductor interface with corrosion products forming the semiconductor. Both of these mechanisms help explain the low and high frequency corrosion effects from a macroscopic point of view.
Nathan IDA is Distinguished Professor of Electrical and Computer Engineering at The University of Akron in Akron, Ohio. His research work encompasses the broad aspects of computational electromagnetics where he has contributed to both understanding of the interaction of electromagnetic fields with materials and to the development of new methods and tools for numerical modeling and simulation for, and beyond. An important part of this work is in electromagnetic nondestructive testing and evaluation of materials at low and microwave frequencies with particular emphasis on theoretical issues, on all aspects of modeling and simulation and on related issues stemming from research in NDE including sensors and applications. Other areas of current interest include electromagnetic wave propagation, theoretical issues in computation, as well as in communications and sensing. Much of this work has found its way into practice through industrial relations and consulting across industries as diverse as power generation, polymers, steel, medical and software. Dr. Ida has published extensively on electromagnetic field computation, nondestructive testing of materials, surface impedance boundary conditions, sensing and others, in over 400 publications. He has written 12 books including two on computation of electromagnetic fields (one in its second edition) one on modeling for nondestructive testing, one on nondestructive testing with microwaves, a textbook on engineering electromagnetics, now in its fourth edition, a textbook on sensing and actuation (now in its second edition) a book on the theory and applications of surface impedance boundary conditions and others including on ground penetrating radar and industrial sensing based on microwaves.
Current interests also include work on NDE 4.0 and, in particular on the advancement of NDE into the digital age. Dr. Ida is a Life Fellow of the Institute of Electric and Electronics Engineers (IEEE), a Fellow of the American Society of Nondestructive Testing (ASNT), a Fellow of the Applied Computational Electromagnetics Society (ACES) and a Fellow of the Institute of Electronics and Technology (IET). Dr. Ida teaches Electromagnetics, Antenna Theory, Electromagnetic Compatibility, Sensing and Actuation as well as Computational Methods and Algorithms.
Current interests also include work on NDE 4.0 and, in particular on the advancement of NDE into the digital age. Dr. Ida is a Life Fellow of the Institute of Electric and Electronics Engineers (IEEE), a Fellow of the American Society of Nondestructive Testing (ASNT), a Fellow of the Applied Computational Electromagnetics Society (ACES) and a Fellow of the Institute of Electronics and Technology (IET). Dr. Ida teaches Electromagnetics, Antenna Theory, Electromagnetic Compatibility, Sensing and Actuation as well as Computational Methods and Algorithms.
