[en] In the case of a loss-of-coolant accident (LOCA) in a light water reactor, the fuel rod cladding may reach temperatures which cause ballooning and rupture. To investigate the potential azimuthal temperature difference on the surface, a series of calculations were performed using the FRAP-T4 (Fuel Rod Analysis Program Transient) computer code. FRAP-T4 is capable of simulating the state of fuel rods during a LOCA, in particular the two-dimensional (r - theta) temperature distribution. Most of the effects relevant to LOCA behavior are modeled in the code. The calculations were performed for a fuel rod typical of a 17 x 17 pressurized water reactor (PWR) fuel assembly subjected to simplified blowdown thermal hydraulic conditions