  Bubble formation and detachment at a submerged orifice exists widely in both
daily life and academic research, and the influence of solid surface on bubble
formation and detachment has also been extensively investigated. For example,
it has been observed that the bubble on a hydrophobic surface is larger than
the one on a hydrophilic surface. However, this phenomenon is not sufficiently
explained in existing literature. To explain it, we redefine the capillary
force at the orifice edge and the adhesive force between bubble and solid.
Subsequently, we are able to establish an approach that quantitatively explains
the relation between bubble volume and surface wettability. In addition, we
also suggest an alternative mechanism of bubble pinch-off. In our opinion, the
formation of bubble neck during pinch-off may be due to three-phase equilibrium
at the orifice edge, and the breakup of bubble neck may result from the
stretching action of the upward buoyancy force and the downward capillary
force.
