“…The hypervapotron uses internal water cooling along with a series of fins and cavities perpendicular to the flow to maximize the heat transfer capability. However, under such high heat flux conditions, the surface reaches the incipient boiling temperatures of the water, which results in both boiling in the fluid at adjacent to the fin and a large enhancement of heat transfer [1][2][3][4][5][6]. Thus, the design of the hypervapotron for ITER FW application requires the determination of heat transfer in the subcooled boiling regime.…”