Abstract

A total number of 18 experimental fuel assemblies (FAs), containing mixed nitride fuel rods with claddings of various geometry, were irradiated in an BN-600 core. By the end of 2022, JSC SSC NIIAR had completed the post-reactor studies of 16 ETVS BN-600 nitride fuel rods, 4 fuel rods with a gas sublayer irradiated in the composition of OU‑1 and OU‑2 collapsible irradiation devices, and 3 OU‑4 BOR-60 fuel rods with a liquid metal sublayer. Post-reactor studies of nitride fuel rods were preceded by pre-test calculations of their stress-strain and temperature states, taking into account the actual irradiation parameters. The results of the studies were compared with the calculated data. Fuel radiation swelling represents one of the most important factors that determine the degree of thermomechanical interaction between the fuel and the cladding, thus limiting the performance of nitride fuel rods. The present article summarizes and analyzes the currently obtained data on the swelling and its rate for mixed uranium-plutonium nitride fuel in fuel rods with a gas sublayer.

中文翻译：

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基于实验 BN-600 和 BOR-60 燃料棒的反应堆后研究确定混合氮化物铀-钚燃料的膨胀

摘要

总共 18 个实验燃料组件 (FA)，包含具有各种几何形状包层的混合氮化物燃料棒，在 BN-600 堆芯中进行了辐照。到 2022 年底，JSC NIIAR 完成了 16 根 ETVS BN-600 氮化物燃料棒、4 根带有气体子层的燃料棒的反应堆后研究，这些燃料棒由 OU-1 和 OU-2 可折叠辐照装置组成，以及3 OU-4 BOR-60 燃料棒，带有液态金属底层。在氮化物燃料棒的反应堆后研究之前，先对其应力应变和温度状态进行预测试计算，同时考虑到实际的辐照参数。将研究结果与计算数据进行比较。燃料辐射膨胀是决定燃料和包壳之间热机械相互作用程度的最重要因素之一，从而限制了氮化物燃料棒的性能。本文总结并分析了目前获得的关于具有气体子层的燃料棒中混合铀钚氮化物燃料的膨胀及其速率的数据。