An experimental examination of the loss-of-flow accident phenomenon for prototypical ITER divertor channels of Y=0 and Y=2

This paper discusses the thermal response of two prototypical International Thermonuclear Experimental Reactor (ITER) divertor channels during simulat ed loss-of-flow-accident (LOFA) experiments. The thermal response was chara cterized by the time-to-burnout (TBO), which is a figure of merit on the mo ckups' survivability. Data from the LOFA experiments illustrate that (a) th e pre-LOFA inlet velocity does not significantly influence the TBO, (b) the incident heat flux (IHF) does influence the TBO, and (c) a swirl tape inse rt significantly improves the TBO and promotes the initiation of natural ci rculation. This natural circulation enabled the mockup to absorb steady-sta te IHFs after the coolant circulation pump was disabled. Several methodolog ies for thermal-hydraulic modeling of the LOA were attempted.