Investigation of the Dynamic Characteristics of CANDU Fuel Bundle

CANDU燃料束动态特性研究

• 批准号: 543934-2019
• 负责人: Mohany, Atef
• 金额: $ 2.8万
• 依托单位: University of Ontario Institute of Technology
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=720838
• 关键词: Investigation; Dynamic; Characteristics; CANDU; Fuel

There has been a history of failures in CANDU fuel bundles and chronic cracking of fuel bundle end-plates. Most of these failures were attributed to the acoustic pressure pulsations generated by the primary system heat transport pumps. For example, in 1990, one of the fuel bundles in the Darlington nuclear power plant was damaged as a result of excessive vibration of the fuel elements. The fuel bundle endplates were found broken and subsequent inspections found severe wear marks in a few fuel channels in Units 1 and 2. The cracks in the fuel bundle endplates were caused by axial response of the fuel bundle, which was triggered by acoustic pressure pulsations generated at the primary heat transport (PHT) vane-passing frequency. More recently, endplates cracking in some fuel bundles has been observed at Bruce Power Nuclear Generating plant. The fuel bundle vibration problem that results in end plate cracking is exasperated if an external excitation frequency, such as that generated by the PHT pumps, matches one of the natural vibration frequencies of the fuel bundle. As such, the precise knowledge of the dynamic characteristics of the fuel bundle is of paramount importance to devise effective mitigation techniques that can be implemented to alleviate this issue. Up to date there is little knowledge, if any, about the dynamic characteristics of fuel bundles and the effect of radiation on their response. Therefore, the main objective of this project is to experimentally and numerically investigate the dynamic characteristics of CANDU fuel including the effect of radiation on the fuel bundles dynamics. The output of this project will provide a much needed information about the fuel bundle characteristics to aid existing CANDU operators to manage and mitigate the vibration problems and the end plate cracking issue of fuel bundles. This will not only support the increased safety and reliability of CANDU fuel bundles, which will directly benefit the Canadian economy, but could also be used in future CANDU reactors to avoid fuel bundle failures.

CANDU 燃料棒束曾发生过故障，燃料棒束端板长期开裂。这些故障大部分归因于主系统热传输泵产生的声压脉动。例如，1990年，达灵顿核电站的一个燃料束因燃料元件过度振动而损坏。发现燃料棒束端板破裂，随后的检查发现1号和2号机组的几个燃料通道有严重磨损痕迹。燃料棒束端板的裂纹是由燃料棒束的轴向响应引​​起的，该响应是由产生的声压脉动触发的在主要热传输 (PHT) 叶片通过频率下。最近，在布鲁斯电力核发电厂观察到一些燃料束的端板破裂。如果外部激励频率（例如由 PHT 泵产生的频率）与燃料棒束的固有振动频率之一匹配，则导致端板破裂的燃料棒束振动问题会加剧。因此，准确了解燃料棒束的动态特性对于设计可缓解这一问题的有效缓解技术至关重要。迄今为止，对于燃料束的动态特性以及辐射对其响应的影响知之甚少（如果有的话）。因此，该项目的主要目标是通过实验和数值研究 CANDU 燃料的动态特性，包括辐射对燃料束动力学的影响。该项目的成果将提供有关燃料棒束特性的急需信息，以帮助现有 CANDU 运营商管理和减轻燃料棒束的振动问题和端板破裂问题。这不仅将支持提高 CANDU 燃料棒束的安全性和可靠性，从而直接使加拿大经济受益，而且还可以用于未来的 CANDU 反应堆，以避免燃料棒束故障。