A useful simplification in the analysis of the motion of boiling coolant in a channel is slip hypothesis. Unfortunately, many complex empirical slip ratio correlations make the solution of two-phase flow problems quite difficult. A suitable fitting for all these correlations is proposed in this work, thus reducing the problem to one of elementary quadratures. A short analysis is performed about the steady-state initial condition concept, and a more correct definition of it in time-dependent initial value problems is suggested.
