A fast running computer code for steady state thermohydraulics in U-tube steam generators

This paper deals with the analysis of thermal hydraulics in PWR U-tube steam generators, performed by a computer code. This code provides the enthalpies (temperatures and steam qualities) of both fluid in the cold and hot leg. The mathematical model, deduced by the energy and momentum balance equations, is accurately described; the numerical procedure for the integration of these equations is related in its main features. Finally some details concerning the use of the code are discussed and the results obtained for two steady state working conditions of the steam generator, are presented. The numerical predictions show a good agreement with the data available in literature