基于中子噪声分析的某核电厂堆芯吊篮梁型振动特征研究

研究了基于堆外电离室中子噪声信号监测压水堆核电厂反应堆吊篮的方法,通过计算电离室中子噪声的互功率密度谱、相干和相位,分析得到了堆芯吊篮梁型振动的频率;利用该方法,计算获得了某正常运行状态下压水堆核电厂换料周期内堆芯吊篮梁型振动频率和中子噪声功率谱幅度的变化趋势,结果说明了在反应堆正常运行状态下,随着堆芯燃耗的增加,吊篮梁型振动频率发生了微小漂移,频率变小,该频率处中子噪声功率谱幅度变大。

Study on Character of Core Barrel Beam Mode Vibration During PWR Refueling Cycle

The method of monitoring core barrel of PWR is studied based on neutron noise which is from ex-core neutron detector.Through aclculating CPSD,coherent and phase of the relative channel ionization chamber,the frequency of core barrel beam mode vibration is obtaioned.With the method,we calculated the trends of core barrel beam vibration frequency and CPSD amplitude in PWR refueling cycle under normal operation state.The results illustrate that in the condition of normal operation of reactor,the core barrel beam vibration frequency turns out to drifts and decreases,and the magnitude of CPSD at this frequency along with corresponding the core burnup increasing.