Ivan Alessio Maione

A New Approach for Characterizing the Energetic Magnetic Behavior of Fe-9Cr Steel Under Transient Conditions

The aim of this paper is to evaluate the magnetic properties and losses of the Fe-9Cr steel under nonperiodic conditions of the magnetic field. A new approach combining an optimized linear problem and the properties of the classical Preisach theory is adopted and described. An experimental analysis is carried out to characterize quasi-static major loop and dynamic cycles obtained at different rates of the driving magnetic field H. After a series of quasi-static major loops, dynamic cycles are defined in a first case, varying H from the saturation to its opposite value, and in a second case, forming minor asymmetric loops. In both the cases, hysteresis and eddy current losses are estimated via the proposed method. Total losses are compared with measurement results to validate the procedure.

Overview of the HCPB Research Activities in EUROfusion

In the framework of the EUROfusion’s Power Plant Physics and Technology, the working package breeding blanket (BB) aims at investigating four different BB concepts for an EU demonstration fusion reactor (DEMO). One of these concepts is the helium-cooled pebble bed (HCPB) BB, which is based on the use of pebble beds of lithiated ternary compounds and Be or beryllides as tritium breeder and multiplier materials, respectively, EUROFER97 as structural steel and He as coolant. This paper aims at giving an overview of the EU HCPB BB Research and Development (R&D) being developed at KIT, in collaboration with Wigner-RCP, BUTE-INT, and CIEMAT. The paper gives an outline of the HCPB BB design evolution, state-of-the-art basic functionalities, requirements and performances, and the associated R&D activities in the areas of design, functional materials, manufacturing, and testing. In addition, attention is given also to the activities dedicated to the development of heat transfer augmentation techniques for the first wall and the corresponding testing. Due to their nature as design drivers, a brief overview in the R&D of key HCPB interfacing areas is given as well, namely, the tritium extraction and recovery system, the primary heat transfer and power conversion systems, and safety topics, as well as some specific activities regarding the integration of in-vessel systems through the BB. As concluding remarks, an outline of the standing challenges and future R&D plans is summarized.

Characterization of magnetic properties and losses of Fe-9Cr steel under transient conditions

The aim of this paper is to evaluate the magnetic properties and losses of the Fe-9Cr steel under nonperiodic conditions of the magnetic field. A first series of measurements is performed for characterizing the quasi-static major loop and various dynamic cycles obtained at different rate of the driving magnetic field H. Then, a series of “ad-hoc” experiments is defined in order to provide a good basis for discussion and validation of eddy current and hysteresis losses calculated via analytical methods. In a first case, moving from the saturation H is rapidly changed at different rates towards the opposite saturation. In a second case, minor asymmetric loops are formed after a series of major cycles. In both the cases, measurements are performed under non periodic conditions. Experimental and simulation results are reported and discussed throughout the paper.