双层安全壳环廊泄漏率分析方法研究

Research on Double Containment Annulus Leakage Rate Test

双层安全壳核电机组的环廊密封性是核安全的重要保证,需要准确测量以验证其与设计的符合性。本文以压差和流量之间的二次函数理论为基础推导了环廊负压和时间的函数关系,并利用此函数计算了环廊密封性试验期间内外压力平衡过程中各时间点的泄漏率,同时对环廊负压参考端的压力特性进行了分析,提出了带环廊负压修正的拟合方案。某核电厂实测数据验证结果表明,使用带环廊负压修正的二次函数拟合方案进行环廊泄漏率分析时精度较高。

The tightness of the double containment annulus is critical to the safety of nuclear power plants,and the test procedure and data analysis should be reliable and reasonable.The formulation of the pressure in double containment annulus versus time is deduced in this paper with the foundation of the quadratic function law of pressure difference and the rate of air flow,which is used to calculate the leakage rate of the annulus at specified time.The fitting of annulus leakage rate against pressure difference is resulted from the analysis of the property of reference point for the measurement of annulus negative pressure.The quadratic theory is verified with project measured data,and is optimised with a corrected pressure difference,which performs better,and is recommended in the calculation of annulus leakage rate test.