Abstract
The selection of radial power reference distribution is an important prerequisite and basic component of reactor safety analysis. In this paper, the reference radial power of a large PWR is calculated and evaluated in detail from 1/4 core and 1/4 hot assembly based on large data, and the following conclusions are drawn: (1) Based on the batch programming calculation of simple random reconfiguration, the influence of 1/4 core power distribution on the minimum DNBR value is negligible. (2) Based on the power capability analysis bank and the three-dimensional core physical accidents banks of rod drop, uncontrolled RCCA withdrawal at subcritical condition, uncontrolled single control rod withdrawal, RCCA ejection, steam line break, the power distributions of 1/4 hot assembly reconstructed by extracting the rod power distributions are evaluated, and it is concluded that the reference radial power distribution has enveloping property. Based on a large amount of data, the reference distribution is studied and evaluated, and it is verified that it can envelop possible distributions to meet the needs of core safety evaluation. Through the above evaluation research, a method to determine the radial power reference distribution of PWR is obtained, which can be used by engineers when designing the reference radial power distribution.