ITER diagnostic port plug engineering design analysis in the EU

Engineering analysis has been carried out on a representative equatorial diagnostic port plug of ITER, outcome of which is given here. A preliminary overview of the work for a prototypical diagnostic upper port plug is also reported. To ensure that the port plug structure satisfies the requirements of the ITER environment, the following analyses have been performed: finite element (FE) analyses of static and dynamic behaviour under electromagnetic loads, FE vibration analysis, FE thermal-structural analysis and nuclear heating and radiation dose studies. The main outcomes from these analyses and consequent design developments are a revision of the stainless steel/water ratio in the plug neutron shielding modules and the incorporation of improved neutron shielding of the port duct, a modification of the port plug top plate arrangement, to increase torsional stiffness of the structure under disruption loads, and improved solutions for cooling arrangements. Manufacturing studies have also been performed, involving the assessment of methods for the production of plug flanges, the analysis of welding techniques for parts assembly and methods for the introduction of cooling features in plug components. Reference design solutions and possible modifications will be presented and discussed