Automatic multi-cycle reload design of pressurized water reactor using particle swarm optimization algorithm and local search

• An automatic multi-cycle core reload design tool, which searches the fresh fuel assembly composition, is developed.
• The search method adopts particle swarm optimization and local search.
• The design objectives are to achieve required cycle energy, minimum fuel cost, and the satisfactory constraints.
• The constraints include the hot zero power moderator temperature coefficient and the hot channel factor.

An automatic multi-cycle core reload design tool, which searches the fresh fuel assembly composition, is developed using particle swarm optimization and local search. The local search uses heuristic rules to change the current search result a little so that the result can be improved. The composition of the fresh fuel assemblies should provide the required cycle energy and satisfy the constraints, such as the hot zero power moderator temperature coefficient and the hot channel factor. Instead of designing loading pattern for each FA composition during search process, two fixed loading patterns are used to calculate the core status and the better fitness function value is used in the search process. The fitness function contains terms which reflect the design objectives such as cycle energy, constraints, and fuel cost. The results show that the developed tool can achieve the desire objective.