On the implementation of numerical schemes for the study of unsteady two-phase flows

This paper deals with the application of numerical schemes to the calculation of two-phase flows through safety systems like blowout diaphragms or safety valves. The problem lays in the modelling of the vaporization of the liquid, this vaporization happens because of the pressure drop when the liquid flows through the safety system. 2 aspects of the problem have been considered, first the delay to the phase transformation due to the quick drop of pressure and secondly the adequate flow equations that can sustain a dramatic change in the Mach number from a few tenths to several units with generation of condensation shock waves. The Roe and the Rusanov solvers have also been used to solve the equations set. (A.C.)