Abstract A 3-D full reactor core simulation of VVER-1000/V-446 during full power normal operation is developed to investigate reactivity control and heat transfer improvements when using silver nanoparticles as the base coolant. Coupled neutronic/thermohydraulics analysis is performed using efficient coupling method in which the detailed neutronic model has been created in MCNP, and porous medium method has been used for the thermohydraulics simulation. Consistent with the porous medium approach, complexity of the thermohydraulics full core simulation fades away and reasonable radial and axial distributions of coolant temperature are obtained applying the distributions of power, which are related to the core neutronics. According to safety margins, the reactor operates safer with nanofluid in comparison with the traditional coolant owing to the higher negative temperature coefficient of reactivity. The outcomes indicate that minimum departure from nucleate boiling ratio using nanofluid is almost 9.5% higher, and nanofluid improves the reactor safety margins.

中文翻译：

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使用 3-D 全核耦合中子和热工水力分析评估纳米流体冷却剂对 VVER-1000/V-446 反应堆的影响

摘要 开发了 VVER-1000/V-446 在全功率正常运行期间的 3-D 全反应堆堆芯模拟，以研究使用银纳米粒子作为基础冷却剂时的反应性控制和传热改进。耦合中子/热工水力分析使用高效耦合方法进行，其中详细的中子模型已在 MCNP 中创建，多孔介质方法已用于热工水力模拟。与多孔介质方法一致，热工水力全堆芯模拟的复杂性逐渐消失，并且应用与堆芯中子学相关的功率分布获得了合理的冷却剂温度径向和轴向分布。根据安全边际，由于反应的负温度系数更高，与传统冷却剂相比，使用纳米流体的反应堆运行更安全。结果表明，使用纳米流体与核沸比的最小偏差几乎高出 9.5%，并且纳米流体提高了反应器的安全裕度。