POTENTIAL INFLUENCE OF THREE-DIMENSIONAL EFFECTS ON PWR LOCA BEHAVIOR

摘要

This report presents the results of a study performed to determine the potential influence of three-dimensional (3-D) effects on pressurized water reactor (PWR) loss-of-coolant accident (LOCA) behavior. The Trojan Nuclear Power Station is utilized as the reference PWR and the influence of 3-D effects is evaluated for the design basis accident. In particular, the influence of uneven axial and radial power distributions and flow blockage is calculated to determine potential 3-D effects on blowdown heat transfer. In addition, the influence of radial flow in the core, entrained liquid behavior in the reactor upper plenum, loop hot leg, and steam generator inlet plenum is calculated to determine potential 3-D effects on re flood heat transfer. One-dimensional system and multidimensional component computer codes are used to perform the calculations. On the basis of the results of these analyses, recommendations are made regarding the need (or lack thereof) for new water reactor safety research experiment facilities.