مدل‌سازي قلب راكتور هسته‌اي بوشهر با استفاده از سوخت TVS-2M و بهينه‌سازي تركيب سوخت و مكان براي بارگذاري يك مجتمع سوخت UTVS در قلب اين راكتور

Modeling the Bushehr Nuclear Reactor Core with TVS-2M Fuel an‎d Optimizing Fuel Composition an‎d Placement for Loading a UTVS Fuel Assembly in the Reactor Core.

مهندسي هسته اي

Nuclear fuel is a highly complex material that is continuously undergoing development an‎d is produced by a wide range of manufacturers. The core of an operational power plant can contain hundreds of fuel assemblies; in cases where more than one type of fuel assembly design is present in the core, it is described as a mixed core. Ensuring that the different types of fuel assemblies do not interact in a harmful manner, which could lead to operational issues in the reactor core, is a critical aspect of nuclear safety assurance. In this study, the modeling of the core number 13 of the Bushehr Nuclear Reactor was conducted using TVS-2M fuel assemblies, with the aim of optimizing the loading of a UTVS fuel assembly in terms of fuel composition an‎d placement within the reactor core. The objective was to ensure that the UTVS assembly is subjected to the least possible neutronic, thermohydraulic, an‎d thermomechanical stresses while maintaining the coreʹs efficient operation. To achieve this, after conducting relevant studies, the core number 13 of the Bushehr reactor was modeled using the Dragon an‎d PARCS codes for neutronics calculations. The UTVS assembly was loaded into various positions within the core with different fuel enrichments an‎d analyzed accordingly. Subsequently, for each of the mixed cores generated in the neutronics calculations, the equivalent hot channel of the reactor core an‎d the hot channel of the loaded UTVS assembly were examined thermal hydraulically using the ANSYS FLUENT software. Following this, the hot fuel rod of the UTVS assembly was modeled in the FRAPCON code for each scenario, an‎d thermomechanical analyses were performed. Finally, an artificial neural network was developed using the output parameters from the neutronics, thermal hydraulics, an‎d thermo-mechanics calculations. By coupling this network with a genetic algorithm an‎d selec‎ting an appropriate cost function, optimization was carried out to determine the optimal position an‎d fuel enrichment for loading the UTVS assembly in the core number 13 of the Bushehr reactor. The optimal configuration for loading the UTVS assembly was determined to be at position 16 of the core number 13 with a fuel enrichment of 2.4%. Finally, fuel consumption calculations were performed for the optimized mixed core over the operational cycle an‎d compared with the original core. This optimization led to improvements in certain core parameters with the new fuel assembly loading, as well as ensuring that the new fuel assembly is subjected to minimal stresses, thermal conditions, an‎d neutronics concepts.

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