核电厂堆芯出口温度测量表征性分析

Characterization Analysis of Core Outlet Temperature Measurement in Nuclear Power Plants

堆芯出口温度测量对于掌握反应堆运行状态有着重要的意义,本文通过计算流体动力学(CFD)方法对堆芯出口温度测量的表征性进行分析。通过对燃料组件及仪表管结构进行模拟计算,获得了仪表管内冷却剂流场和温度分布;通过对9种典型功率分布下堆芯出口温度测量结果的定量分析,获得了堆芯出口温度表征性与燃料组件功率的关系。结果显示,测点平均温度与燃料棒功率基本呈线性关系,其测点温度随燃料棒功率的增加而增加,测温表征性随燃料棒功率的升高而变差。研究结果为堆芯出口温度测量的校正提供了一定的依据。

The core outlet temperature measurement is of great significance for mastering the reactor operation status.This paper analyzed the characterization of the core outlet temperature measurement by computational fluid dynamics(CFD)method.By simulating the structure of the fuel assembly and instrument tube,the coolant flow and temperature distributions in the instrument tube were obtained.The relationship between core outlet temperature characterization and fuel assembly power was obtained through quantitative analysis of core outlet temperature measurement results under 9 typical power distributions.The calculation results show that the average temperature of the measurement point is basically linearly related to the power of the fuel rod,and the temperature value of the measurement point increases with the increase of the power of the fuel rod,while the characterization of the temperature measurement becomes worse with the increase of the power of the fuel rod.The research results provide a certain basis for the calibration of outlet temperature measurement.