Abstract The Zirconium isotopes have been widely used in many PWR fuel cladding materials. Ignoring the resonance self-shielding effect for Zirconium isotopes, it may introduce 100–300 pcm errors in PWR reactivity predictions. The reference dilution cross section, equivalence theory, and subgroup method can be used in treating resonance self-shielding effect for Zirconium isotopes. Hence, it is important to determine the application and accuracy of these methods. In this paper, the three methods are tested with the DRAGON5.0.1 code based on the different PWR cases. The result of reactivity and absorption cross section is then compared with the Monte-Carlo code cosRMC. It indicates that the resonance self-shielding effect for Zirconium isotopes is related to the cladding region’s thickness, cladding material’s nuclide density, and water/uranium ratio. The equivalence theory and subgroup method are more flexible in treating the resonance self-shielding for Zirconium isotopes. The reference dilution cross section is limited to the typical PWR cases with a specific geometry, nuclide density, and water/uranium ratio. It is demonstrated that the equivalence theory and subgroup method can accurately treat the resonance self-shielding effect for Zirconium isotopes.

中文翻译：

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锆同位素压水堆包层材料共振自屏蔽效应研究

摘要 锆同位素已广泛应用于许多压水堆燃料包壳材料中。忽略锆同位素的共振自屏蔽效应，它可能会在 PWR 反应性预测中引入 100-300 pcm 的误差。参考稀释截面、等效理论和亚群方法可用于处理锆同位素的共振自屏蔽效应。因此，确定这些方法的应用和准确性很重要。本文根据不同的PWR情况，用DRAGON5.0.1代码对这三种方法进行了测试。然后将反应性和吸收截面的结果与蒙特卡罗代码 cosRMC 进行比较。表明锆同位素的共振自屏蔽效应与熔覆区的厚度、熔覆材料的核素密度、和水/铀比例。等价理论和亚群方法在处理锆同位素的共振自屏蔽时更加灵活。参考稀释截面仅限于具有特定几何形状、核素密度和水/铀比的典型压水堆情况。证明了等效理论和亚群方法可以准确地处理锆同位素的共振自屏蔽效应。