  A liquid poured from a curved solid surface can separate as a steady jet or
sheet, or trickle down along the solid surface. It was shown by Duez et al.
[Phys. Rev. Lett. 104, 084503 (2010)] that surface wettability controls the
separation of an inertial flow from a solid surface to an unexpected degree,
which was further motivated by an inertial-capillary adhesion model. In this
paper we extend the analysis by a control volume calculation that takes into
account the velocity profile within the flowing layer, supported by Boundary
Integral potential flow simulations, and the detailed capillary forces induced
by the local curvatures of the sheet. Our analysis captures the appearance of a
critical Weber number below which no steady separated solutions can be
sustained. We investigate the dependence of the critical Weber number on the
wettability and sharpness of the edge of the curved solid, and recover the key
experimental trends.
