Hypothesis of Gümbel is a statement of the initial state of an incompressible fluid film as governed by the hyperbolic differential equation. Olsson’s interphase condition, upon providing cross-boundary interface continuity, targets the Swift-Stieber state at the rupture boundary with a nonvanishing speed that is a function of the postulated cavitation morphology model; experimental photographic records suggest the rolling stream concept which combines an adhered film immediately downstream of the boundary and striated streams farther on. To study cavitation without end-leakage effects, the pre-incipience contiguous fluid film solution is given by the Sommerfeld solution with the ambient state and is reduced to the π-film, and the issue of post-incipience evolution is reduced to an appropriate interpretation of a suitably defined evolution time. To treat cavitation with allowance for end-leakage effects, computation of the pre-incipience contiguous film requires a two-dimensional adaptation of the Sommerfeld solution with a consistent spline interpolation scheme, and treatment of Olsson’s interphase condition is quite elaborate.
Part of the book: Cavitation