Study of the CPR1000 complete loss of coolant flow accident based on sampling statistical method

During the complete loss of coolant flow accident (LOFA) in CPR1000 plant, the coolant flow rate would be decreased, the temperature and pressure would be increased, which could cause the departure from the nucleate boiling (DNB). This paper uses the system code GINKGO and the sub-channel code LINDEN, both developed by China General Nuclear Power Group, to establish the model of the CPR1000 plant and to calculate the transients DNBR of the complement loss of flow accident. And the uncertainties of some key-parameters are analyzed by the sampling statistical method when DNBR reaches the minimum value. The transient code uncertainty, the sub-channel code uncertainty and the CHF correlation uncertainty are also concerned. The results show that there is no DNB phenomenon but much DNBR margin during the complete loss of coolant flow accident in CPR1000 plant, and it is acceptable to introduce the statistical method to complete of flow accident analysis of CPR1000. (authors)