Fusion Science and Technology / Volume 64 / Number 2 / August 2013 / Pages 309-314
Divertor and High-Heat-Flux Components / Proceedings of the Twentieth Topical Meeting on the Technology of Fusion Energy (TOFE-2012) (Part 1), Nashville, Tennessee, August 27-31, 2012
The impact of Be tile size on the stress exerted on the CuCrZr heat sink for the ITER EHF finger was examined. The study especially focused on the areas beneath the tiles that are exposed to the high convective heat flux. For reference, in a Be tile size of 50x50x8 mm3, the calculated equivalent strain range using elastic analysis for the path of interest through the side wall of the CuCrZr heat sink resulted in a peak value at the inner wall of ~0.492%. The corresponding fatigue lifetime of the heat sink locally is unacceptably low, 1400 cyclic operations. By using smaller tiles, lower stress amplitudes are observed due to a smaller deformation. In this paper, the total strain range under ITER projected pulsed operating conditions is analyzed for a range of Be tile sizes. The analysis model uses a complete pair of twin fingers as opposed to a sub-model of two tiles. The paper documents the calculated cyclic lifetime of the ITER EHF CuCrZr heat sink with respect to Be tile size and peak heat loads by evaluating the total strain range both from elastic and time independent elasto-plastic analyses for repeated cycle.