In addition to the mechanisms corresponding to nucleate boiling
and convective boiling contributions, recently, a three-zone
flow boiling model based on the elongated bubble flow regime,
was developed by Thome et al. [16] and Dupont et al. [17] to predict
heat transfer characteristics in micro-channels. The point they
make is that heat transfer is controlled primarily by conduction
through the evaporation film trapped between the elongated bubble
and the tube wall.