Modelling the kinetics of microstructure evolution and irradiation damage within Zr cladding for nuclear fuel

核燃料 Zr 包壳内微观结构演化和辐照损伤动力学建模

• 批准号: 2598106
• 金额: --
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2598106
• 关键词: Modelling; kinetics; microstructure; evolution; irradiation

This research will investigate the kinetics of microstructure evolution and irradiation damage within Zr cladding of nuclear fuel rods. Understanding Zr behaviour is key for next generation of nuclear reactors, especially Small Modular Reactors (SMRs), where fuel design has yet to be decided. Statistical models of phase transformation will be coupled with continuum models of diffusion to assess kinetics across the cladding, utilising multi-component descriptions of diffusion. A thermodynamic database will be used to determine phase stability, equilibrium compositions, and ultimately the chemical driving forces for phase transformations. Development of a mobility database will be explored to complement the existing thermodynamic database. Through implementing a thermodynamic description of kinetics, it is possible to capture the evolution of multiple metastable and equilibrium phases. The modelling will explore different hypotheses regarding the kinetics of irradiation damage within the Zr cladding. The models will be developed and validated against experimental data generated by National Nuclear Laboratory (NNL) from inservice reactor cladding. Understanding the kinetics of irradiation damage is vital in enabling informed decisions regarding component lifespan, both in reactor and after removal during storage. This work will steer decisions for the type of fuel cladding used in SMRs, as well as the lifespan and subsequent storage considerations. Finally, this project also has the advantage of being modelling based, and hence achievable given the current COVID restrictions.

本研究将研究核燃料棒 Zr 包壳内微观结构演变和辐照损伤的动力学。了解锆的行为是下一代核反应堆的关键，特别是小型模块化反应堆（SMR），其燃料设计尚未确定。相变的统计模型将与扩散的连续模型结合起来，利用扩散的多分量描述来评估包层的动力学。热力学数据库将用于确定相稳定性、平衡组成，并最终确定相变的化学驱动力。将探索开发流动性数据库以补充现有的热力学数据库。通过实施动力学的热力学描述，可以捕获多个亚稳态和平衡相的演化。该模型将探索有关 Zr 包层内辐照损伤动力学的不同假设。这些模型将根据国家核实验室（NNL）从在役反应堆包壳生成的实验数据进行开发和验证。了解辐照损伤的动力学对于做出有关部件寿命的明智决策至关重要，无论是在反应堆中还是在存储过程中移除后。这项工作将指导中小型反应堆中使用的燃料包壳类型的决策，以及使用寿命和随后的存储考虑。最后，该项目还具有基于建模的优势，因此在当前新冠疫情限制下是可以实现的。