蒸汽发生器传热管流弹失稳计算

摘要

蒸汽发生器管束一旦出现流弹失稳现象，可以在很短的时间内破坏传热管的完整性，影响核电站安全。因此，在设计蒸汽发生器时要预测与防止传热管流弹失稳现象。通过有限元软件ANSYS的梁单元建立传热管模型，进行模态分析并提取相关结果；然后将模态分析的结果代入MATLAB计算传热管流弹不稳定率并和专用软件进行对比。该方法计算结果与专用软件吻合，且分析表明套筒开口区与弯管区流速对流弹不稳定率影响较大；管子高频时不易发生流弹失稳现象。%If the fluidelastic instability (FEI)phenomenon appears in the steam generator tubes,the in-tegrity of tube would be destroyed in a short time,meanwhile impacting the safety of nuclear power plant. For the reason,prediction and prevention of the phenomenon -FEI in designing steam generator is very necessary.The specific method is to build the tube′s model by the beam element of ANSYS,perform the tube′s modal analysis,extract relevant result,and then take the result into MATLAB to simulation the FEI,finally compare the result with special software.The result of this method is close to the special soft-ware,and the analysis show that the fluid velocity at wrapper opening region and U -bend region has great impact on the FEI;The FEI is less prone to appear at high frequency mode.