Safety assessment of disruption energy fluxes on in-vessel components with SAFALY

SAFALY is a hybrid code comprising a zero dimensional plasma dynamics and a radial and poloidal thermal analysis of in-vessel components. It was initially adopted to assess ITER EDA plasma abnormal events from the safety point of view and was progressively improved to analyze several accident scenarios by considering a wide range of phenomenology such as burn control or transport of impurities. Recently, the Fusion Energy Engineering Laboratory (FEEL) of the Universitat Politecnica de Catalunya has retrieved SAFALY for ITER 500 MW in order to evaluate sequences challenging the integrity of the vacuum vessel and the other in-vessel components. From 2005 up to now, the FEEL has modelled the first wall, the blanket and the divertor as a combination of layers of beryllium, copper, SS 316L-IG, coolant channels and thermal gaps. Evolution of the temperature and safety margins of the plasma facing components have been simulated when fuelling abnormalities, such as overfuelling by a factor 1.5, overfuelling by a factor 3 and sudden suspension of fuelling occurs [01]. Validation of the plasma core with ASTRA shows high grade of coherence. Among the improvements it's also worthwhile to mention the implementation of a user graphic interface. In this contribution, the model of the energy fluxes on the plasma facing components during disruptions is upgraded. Particularly, extrapolation from latest measurements of disruptions resulting from the collapse of Internal Transport Barrier (ITB) in JET have been considered because it seems that conduction to the first wall and limiter has severe implications in that case. Data from multi-machine comparisons that predict the average disruption energy flux in ITER and direction of plasma in Vertical Displacement Event after the thermal quench of major disruptions have been also considered. In order to reduce uncertainties and conservatism of the results, further minor changes have been incorporated to allow a more accurate evaluation of the influence of additional incoming D-T fuel in the plasma during the accident transients. Several scenarios of abnormal fuelling events and ex-vessel loss-of-coolant accidents in divertor and limiter have been assessed by considering all these factors. (author)