Two-phase flow modeling of a vertical channel by Relap5 code system

It is known, that the phenomena of phase change and boiling crisis are not yet fully deciphered, which leads to generation technical problems, such as frequent breakdowns accidental shutdowns in thermal installations. The main objective this study numerical analysis an ascending flow during a vertical channel by Relap5/Mod3.2 code. This code can helps heat transfer convection, boiling, condensation even radiationin steady state or transition regimes. validation was made comparing our results simulationwith experimental under same conditions (pressure, mass flow, diameter flux density). allowed us determine different regimes along channel, well appearance crisis.