控制棒下落时间计算模型

Calculation model of controlling rod drop time

反应堆驱动线是反应堆控制的"生命线",执行重要的安全功能。控制棒下落时间不仅是驱动线设计考核的重要指标,也是核电站安全分析的关键参数。基于压水堆驱动线的结构特性,对控制棒组件在下落过程进行受力分析,提出落棒时间计算的数学模型,采用有限差分法求解运动方程,并且在此基础上编制计算程序。计算结果最终表明:程序计算值与岭澳核电站二期机组热态落棒试验值符合较好,基于此计算方法编制的落棒时间计算程序可以用于压水堆停堆时的安全评价。

Background： Reactor drive line is the ＂lifeline＂ of reactor control, which performs important safety functions. Purpose： To provide the basis for the drive line design assessment and nuclear power plant safety analysis. Methods： Through analyzing the stress of pressurized water reactor control rod assembly and control rod drive mechanism, established the mathematical model and the motion equation, and then solved by the finite difference method. Results： The program calculated value accords well with the test value of Ling＇ao nuclear power plant phase II unit hot rod drop. Conclusion： The rod drop time of calculation program based on this method can be used to the safety evaluation when pressurized water reactor is shut down.