Development of Core Simulator (CoSi) for APR1400 And Analysis of LPPT Result using APR1400-CoSi

According to NRC guidelines, Low Power Physics Test (LPPT) is required to be performed in low temperature/low pressure (160 .deg. C/42.2 kg/cm²) as well as NOT/NOP (291.3 .deg. C/158.2 kg/cm²) because Shin-Kori Unit 3 is FOAK nuclear power plant. Low Power Physics Test (LPPT) is essential to verify the nuclear design and robustness of reactor safety. LPPT consists of initial criticality, Point of Adding Heat (POAH), All Rod Out (ARO) Boron Concentration, Isothermal Temperature Coefficient (ITC), Control Rod Worth measurements and so on. KHNP-CRI has developed the Core Simulator for APR1400 (APR1400-CoSi) in order to improve the ability performing the LPPT. Especially, APR1400-CoSi has enhanced capability to calculate the full Core neutronic parameters by revising RAST-K that is three dimensional real time core kinetic program. APR1400-CoSi has been developed for education-training of Low Power Physics Test(LPPT). Particularly, APR1400-CoSi has an enhanced capability to calculate the full core neutronic parameters by revising RAST-K which is a three dimensional real time core kinetics program. Low Power Physics Test (LPPT) was performed using APR1400-CoSi and the results showed very similar values with the predicted ones. In other words, the initial core model of Shin-Kori Unit 3 in APR1400-CoSi system has been verified to be appropriate enough. Also, it was confirmed that the test range of Low Power Physics Test (LPPT) reamains effective even though the largest incremental bank reactivity is inserted in core by analyzing the power change during the rod SWAP test