Validation of WCOBRA/TRAC-TF2 on Boil-off Heater Rod Dryout and Heatup Using Semiscale S-07-10D Test
This paper discusses the assessment of the capability of the best estimate reactor thermal hydraulic code WCOBRA/TRAC-TF2 in predicting the core heater rod dryout and the subsequent post dryout heatup during the boil off transient in a simulated pressurized water reactor (PWR) small break loss of coolant accident (LOCA) test. The test being simulated, Semiscale S-07-10D, features an extremely deep core uncovery and corresponding high heater rod temperature of 1060 K (1450 oF). As accurate core mixture level and fuel rod temperature predictions are the key in the analysis of any LOCA scenario, Semiscale S-07-10D became an indispensable element in the WCOBRA/TRAC-TF2 validation test matrix to assess the code’s capability in predicting the highly ranked phenomena of the postulated PWR LOCA accidents. The approach taken in this study utilizes the available test measurements to define pressure and flow boundary conditions at interfaces where the vessel components interacted with the rest of the primary coolant system. This permits focus on the modeling accuracies of the code on achieving high rod temperature due to the two-phase level swell/void distribution and the post dryout heat transfer deterioration. By defining the vessel flow boundary condition in the simulation, the prediction of the rod heatup is unambiguously attributed to the accuracies of the two-phase level swell and post dryout heat transfer models in the simulation code. The WCOBRA/TRAC-TF2 simulation results of two-phase void fraction and heater rod temperatures were compared with the available experimental data at different core elevations. It is shown that the code prediction agrees well with the test data.
WCOBRA/TRAC-TF2 Semiscale LOCA Boil-off Dryout
Liping Cao Katsuhiro Ohkawa Josh Hartz
Westinghouse Electric Company, LLC Monroeville, PA 15146, USA
国际会议
上海
英文
2130-2141
2010-10-10（万方平台首次上网日期，不代表论文的发表时间）