Abstract The Autonomous Circulation Miniature Integrated nuclear Reactor (ACMIR) has features of compact structure, high power density and high efficiency. The reactivity control strategy is an important aspect in the design of ACMIR, which is essential for reactor safe operation. In this paper, two ex-core reactivity control options, namely, the rotating control drums and sliding reflector segments, were investigated. Furthermore, an optimization design was conducted on both strategies, including alternative absorber materials, thickness of absorber, absorber angle and the thickness of reflector. Finally, we analyzed and compared the neutronic characteristics with different control schemes, including the reactivity insertion behavior, reactivity temperature coefficient, submersion criticality and spatial power distribution. This work helps to improve the safety characteristics of ACMIR in reactivity control and operation.

中文翻译：

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热电一体化空间核反应堆反应性控制策略研究

摘要 自主循环微型集成核反应堆（ACMIR）具有结构紧凑、功率密度高、效率高等特点。反应性控制策略是ACMIR设计的一个重要方面，对反应堆安全运行至关重要。在本文中，研究了两种堆外反应性控制选项，即旋转控制鼓和滑动反射器段。此外，对两种策略进行了优化设计，包括替代吸收体材料、吸收体厚度、吸收体角度和反射体厚度。最后，我们分析和比较了不同控制方案的中子特性，包括反应插入行为、反应温度系数、浸没临界和空间功率分布。