NUCIRC Thermal-Hydraulic Applications in Support of CANDU® Plant Design and Operation

Abstract

The NUCIRC thermal-hydraulic code is used during the design stage, the commissioning stage, the operational stage, and the refurbishment stage of CANDU nuclear plants. It provides the basis for many subsequent applications ranging from general safety analysis to main Heat Transport System (HTS) component integrity analyses. Most often the code is used for Critical Channel Power (CCP) analysis in support of Regional Overpower Protection (ROP) trip setpoint analysis. Thermal-hydraulic models representative of the HTS can be updated using site measured data, by employing the many options of this code. Different code options allow the determination of aging for each HTS component and, once combined, all components result in the thermal-hydraulic model of the entire HTS. This paper will discuss each NUCIRC option and how each option is used to define a thermal-hydraulic model representative of site data and how observed HTS component aging trends can be obtained and used for accurate extrapolation to future operation.