要約

This paper reviews work on adiabatic two-phase flow and forced flow boiling in microchannels with hydraulic diameters of the order 0.1 to 1 mm. In contrast to normal channels, stratification does not occur, the flow regimes are insensitive to channel orientation, and plug and slug/bubble train regimes are dominant. Pressure drop and void fraction are reasonably well predicted by models for macrochannels, except in annular or froth flows. In flow boiling, the onset of nucleate boiling (ONB) and onset of significant void (OSV) are more complex than in macrochannels. Critical heat flux in flow boiling has been extensive studied; for low flows it is dominated by film dryout but models developed for film dryout in macrochannels are unlikely to be applicable to microchaimels since many of their constituent relationships (e.g. droplet entrainment and deposition) would be expected to break down for this case.