Measurements of three-dimensional, local subcooled flow boiling heat flux and related critical heat flux for PFCs

The optimized design of one-side-heated plasma-facing components (PFC) is d ependent on knowing the local distribution of inside wall heat flux in the now channels. The local inside wall heat flux can be obtained fron selectiv ely chosen local PFC wall temperatures close to the inside boundary of the flow channel. To this end, three-dimensional thermal measurements for a one -side-heated monoblock were made and show: (1) the three-dimensional variat ion of the wall temperature close to both the heated and fluid-solid surfac e boundaries, (2) the resultant effects of local subcooled flow boiling on the 3-D wall temperature/outside heat flux relationship-one of which is the 3-D wall temperature profile is almost unchanged in the vicinity for incid ent heat nw. levels between the onset to fully developed boiling and CHF an d (3) the occurrence of local CHF and local post-CHF. The monoblock has a 1 80.0 mm heated length, has a 10.0 mm inside diameter, and has a circular-li ke cross-section with a 30.0 mm nominal outside diameter.