压水堆余热排出换热器性能研究

Numerical Investigation of Residual Heat Removal Heat Exchange Capacity in Pressurized Water Reactor Plants

以压水堆余热排出系统为对象,建立管壳式换热器的数学模型。与换热器设计软件HTRI的计算结果进行对比,结果表明该模型可以准确预测管壳式换热器的管壳侧出口温度。总传热系数敏感性计算表明,该参数随管壳侧流量变化而变化,在换热器性能预测时不能当作常数处理,应与工况进行耦合计算。当管壳侧体积流量小于1000 m3/h时,总传热系数对流量较为敏感;当体积流量大于1000 m3/h时,流量的影响则相对较弱。该模型为预测换热器其他工况的换热性能提供基础,为换热设备调试提供指导,为核电厂设计验证及高效安全运行提供可靠依据。

Mathematical model is established for shell and tube heat exchanger of PWR residual heat removal system. Comparison with the calculated results from the design software HTRI for the heat exchanger is conducted, and the results show that outlet temperatures of shell and tube side are precisely predicted. The calculation of overall heat exchanger coefficient sensibility shows that this parameter varies with the flow rates of tube and shell side and it is not＇advisable to keep it as constant value in the simulation. The overall heat exchanger coefficient shall be coupled with the heat exchanger flow and heat exchanging conditions during calculation. The overall coefficient is extremely dependent on the flowrates which is less than 1000 m3/h while it seems to be independent with the higher flowrates. The model can be easily employed to predict other system conditions elsewhere and provide the convenient way for the plant test, design verification and high efficient ooeration of nuclear tmwer plants.