Thermal hydraulics analysis of a helical coil steam generator of a small modular reactor

In the present study, thermal hydraulic investigation of a steam generator of an integral small modular reactor (SMR) has been performed. For this investigation, a helical coil steam generator of IRIS design is selected due to availability of its design parameters in literature. Steam generator model is developed in RELAP5/Mod 4.0. At first, steady state simulation has been performed for this model and results are found in good agreement with the IRIS design data. In order to evaluate the behavior of steam generator under accidental conditions, transient analysis has also been performed. Steam generator performance is assessed for two transients, namely, feed line break (FLB) and loss of flow accident (LOFA). Exponential losses of secondary side pressures (inlet and outlet) are considered for FLB, whereas an exponential loss of primary flow rate is considered for LOFA. The results indicate safe and reliable operation of IRIS steam generator for both transients.