The present document deals with the Relap5/Mod3.2 analysis of the Small Break LOCA
experiment SP-SB-03 performed in SPES facility.
SPES is a PWR simulator (Integral Test Facility) installed at SIET center in Piacenza (I).
Volume scaling and core power scaling factors are 1/427, with respect to the Westinghouse 900
MWe standard reactor.
The experiment is originated by a small break in the cold leg (2" equivalent break area in the
plant) without the actuation of the high pressure injection system. Low pressure injection system
actuation occurs after core dry-out.
The Relap5 code has been extensively used at University of Pisa; the nodalization of SPES
facility has been qualified through the application of the version Relap5/Mod2 to the same
experiment and another test performed in the same facility.
Sensitivity analyses have been addressed to the influence of several parameters (like discharge
break coefficient, time of accumulators start etc.) upon the predicted transient evolution.
Qualitative and quantitative code calculation accuracy evaluation has been performed