  Nucleate boiling heat transfer (NBHT) from enhanced structures is an
effective way to dissipate high heat flux. In the present study, the cavities
behaviours for nucleation on roughened surface are numerically studied on the
entire ebullition cycle based on a phase-change lattice Boltzmann method
without introducing any artificial disturbances. The adopted model is firstly
validated with the Laplace law and the two phase coexistence curve, and then
applied to investigate the effects of cavity structure on NBHT. The bubble
departure diameter, departure frequency and total boiling heat flux of an
ebullition cycle are also explored. It is demonstrated that the cavity widths
and the cavity grooves show significant influence on the features of NBHT.
Cavity with circular groove in the present research shows the best performance
for NBHT in terms of the averaged heat flux and bubble release frequency. When
a specific cavity is combined with other different cavities on roughened
surfaces its nucleation process on different roughened surfaces may differ
greatly.
