MIT pressurizer predictions during insurge transients using TRAC-PF1 code

The pressurizer response of a pressurized water reactor (PWR) plays an important role in determining the pressure history of the primary coolant system. It is important to predict accurate behavior of the pressurizer during accidents and off-normal conditions. The purpose of the present study is to assess the TRAC-PF1/MOD1 best-estimate thermal-hydraulic computer code against the separate effects pressurizer vessel test facility operated at the Massachusetts Institute of Technology. The TRAC predictions showed higher pressure response with well-insulated walls during transient insurges than were measured. The computed temperatures exhibited a fair agreement with the measured axial temperature distributions.