PEMETAAN DISTRIBUSI SUHU DAN DNBR PADA PERANGKAT BAHAN BAKAR AP1000-EU

Abstract

The mapping of DNBR and temperature distribution for EU-AP1000’s fuel assembly was carried out. The development of the human resources capability to understand the NPP design, requires comprehensive characteristic design. The background of this research, is that in order to find the comprehensive NPP characteristic design, to carry out the thermalhydraulics distribution mapping during NPP operation, involving the coolant, cladding and meat temperatures, DNBR and heat flux distribution for one eighth EU-AP1000 fuel assembly on the condition of near beginning of life, hot full power, equilibrium xenon and unrodded core. The EU-AP1000 was chosen as a research object, because of the AP1000 originally was designed by Westinghouse US, however the design control document (DCD) is on approval process by UK regulatory (representative European countries). The design of EU-AP1000 has thermal power of 3400 MWt, the number of fuel assemblies of 157, operation pressure 15.1 MPa. Each EU-AP1000 fuel assembly consists of 264 fuel rods which has 0.95 cm rod diameter and 426.72 cm rod length. The calculation was done using COBRA-EN code for 1/8 of fuel assembly of G-9 position, which has variation rodwise power factor of 1.124 to 1.396, and then from the output was made be a map. The mapping result shows that the maximum meat temperature of 1032.95 ^oC was much lower than the maximum limit design, and the safety margin of minimum DNBR of 4.395 was much higher than the minimum limit design. The heat flux, DNBR and temperature distribution mapping result on normal operation, hot full power and near beginning of life condition were sufficient to response to the distribution mapping ones on the end of life of fuel assembly.