核电站设备冷却水系统热交换器传热性能试验方法研究

设备冷却水系统热交换器传热性能是核电厂运行期间需要监测的一项重要参数。为了解决当前已有试验方法不确定度较大的问题,根据典型CPR1000机组配置,采用热交换器传热模拟计算方法和误差传递计算方法,开展热交换器传热性能试验方法研究。研究发现,出口温度法优于其他试验方法,在热交换器的主要工作区间,由于热负荷远小于设备设计值,所有试验方法的不确定度都偏高。给出了对在役核电厂的建议,应结合试验特点和电厂生产计划优化试验时机的选择,并且将试验测量安排在就地仪控系统,以减小试验的不确定度,降低试验结果无效的可能性。开展污垢热阻与运行时间和热交换器压差之间定量关系的研究,对降低在役核电厂试验频率具有重要意义。

Testing Method Study of Heat Transfer Performance of Heat Exchangers of Component Cooling Water System in Nuclear Power Plant

The heat transfer performance of component cooling water system heat exchanger is one of the most important parameter that needs to be monitored during the operation of nuclear power plant. In order to solve the problem that the great uncertainty, based on typical configuration of CPR1000 unit, transfer performance test methods were studied by heat exchanger transfer simulation and error transfer calculation. It was found that the hot-side export temperature method was superior to others, and the uncertainty of all test methods was relatively high in the main working range of the heat exchanger, for the heat load was much smaller than the design value. The research gives the suggestion to active nuclear power plant: the selection of the test time should be combined with the test characteristics and the production plan of plant, and the test measurement should be arranged in the local instrument control system in order to reduce the uncertainty and decrease the possibility of ineffective the test results. It is of great significance to study the quantitative relationship between fouling thermal resistance and running time and heat exchanger pressure difference to reduce the test frequency in active plants.