ISSN Online: 2377-424X
ISBN Print: 0-89116-130-9
International Heat Transfer Conference 6
COOLANT BOILING CRISIS IN ROD ASSEMBLIES
Resumo
The analysis of experimental data on boiling crisis obtained by different authors using rod assemblies and comparison of these data with our results using a rod assembly with subchannels having the same hydraulic parameters made it possible to find typical laws of operating and design parameters when boiling crisis occurs. A conclusion is drawn relating to a two-phase flow pattern effect upon conditions of boiling crisis onset. A technique of boiling crisis calculation is proposed for water boiling in rod assemblies considering flow patterns of a two-phase mixture, geometry of assemblies, non-uniform heat generation over the length and effect of spacing grids. Most experimental data obtained in our country and abroad for rod assemblies both with uniform and non-uniform heat generation over the length within the pressure range (5.0−18.6) 106 N/m2 and mass velocities 400−5000 kg/(m2s) are described by the calculation technique proposed here with an accuracy sufficient for practical use.