支撑板缝隙对蒸汽发生器热工水力特性的影响

The Influence of Tube Support Plates Gaps on Thermal Hydraulic Characteristics in a Steam Generator

采用CFD方法数值研究支撑板缝隙对蒸汽发生器热工水力特性的影响,获得了一次侧流体温度,二次侧流体温度、传热系数、质量含汽率以及传热管温度等关键热工水力参数的局部分布规律,计算所得出口质量含汽率与大亚湾核电站实际运行参数相符;支撑板缝隙处传热管壁温高于流水孔处,支撑板处传热管外壁温度沿圆周方向变化呈周期性波动,无缝隙结构的波动幅度明显高于有缝隙结构。缝隙处质量含汽率高于流水孔处,而流体平均流速小于流水孔处,导致缝隙中液体不足,增加了支撑板缝隙处杂质浓缩和传热管应力腐蚀的可能。

CFD investigating the influence of tube support plates(TSPs) gaps on thermal-hydraulic characteristics in a steam generator,the simulation reveals key parameter distributions under operating conditions and structural parameters,such as primary temperature,secondary temperature,heat transfer coefficient and steam quality,wall temperature,etc.the calculated steam quality of outlet agrees well with the operating parameter of steam generator at the Daya Bay Nuclear Power Plant.The wall temperature at the TSPs gaps is higher than flow hole,the outer wall temperatures periodically fluctuate around the circumference of the tubes at the TSPs.The wall temperatures amplitude of structure without gaps was significantly higher than structure with gaps.The vapor quality at the TSPs gaps is higher than the flow hole,and the average velocity of fluid is less than the flow hole,resulting in insufficient liquid at the gaps,increased the probability of impurity concentration and tubes stress corrosion.