孔板气蚀诱发核级管道振动和噪声问题研究

Research on Vibration and Noise Issues of Nuclear Pipesdue to Orifice Cavitation

针对在役核电厂出现的核级管道系统强烈振动和噪声导致结构失效的问题,采用“数值模拟优先”的研究方法,通过数值计算分析和实验研究,发现节流孔板气蚀是诱发故障的根本原因,提出了工程改造方案。系统改造后的现场调查和评估显示:在保证系统功能和结构完整性满足设计规范的前提下,管系的振动和噪声已控制在可接受的范围内。

Violent vibration and noise symptoms have been found in a nuclear piping system, which is caused by the cavitation after a throttle orifice. The research and engirieering modification of this issue are presented in this paper. Intensive investigation with numerical and experimental methodologies has been made to find the root cause of the malfunction, and then the modification ways are proposed based on the conclusions of root cause analysis. Field investigation and evaluation after system modification have shown great suppression of the vibration and noise symptoms, while the system function and structure integrity have been validated to meet the requirement of original design code, which demonstrates that the system modification issuccessful. Moreover, a “numerical simulation priority” approach is introduced in the research work and the application of this approach has significantly reduced the time and cost of the whole project.