船用二回路系统全工况热力计算方法及特性分析

Thermal dynamic calculation method and characteristic analysis of marine secondary circuit system under all operating conditions

[目的]为便捷高效地对船用核动力装置二回路系统进行全面的热力计算,[方法]针对船用核动力二回路系统的特点,综合考虑核动力装置主汽轮机组以及各辅助设备,立足几种典型工况下的设备参数和热平衡计算结果,建立二回路系统全工况数学模型,提出一种全工况计算方法。在最高工况和最低工况之间均匀设置多个主机功率,将主机功率作为输入自变量。通过多层嵌套循环实现系统各设备热力参数同步变化,得出全部工况下主要设备的耗汽量、工质在各换热节点的温度以及动力装置总耗汽量和效率等参数随工况变化的规律。分析上述变化规律的原因,并将计算结果与设计值进行对比。[结果]结果表明,系统参数误差较小,满足计算精度要求。[结论]计算方法以及得出的变化规律为二回路系统的参数匹配特性计算和研究提供了思路。

Abstract:[Objectives]In order to carry out the comprehensive thermal calculation of the marine secondary circuit systems of nuclear power plants conveniently and efficiently,[Methods]a thermal dynamic calculation method under all operating conditions is proposed and a mathematical model of a secondary circuit system established on the basis of the features of the secondary circuit systems of marine nuclear power plants,the characteristics of main steam turbine sets and accessory equipment,and the calculation results of equipment parameters and heat balance under several typical operating conditions.Several powers of main steam turbine are set evenly between minimum and maximum operating conditions,and the power of the main steam turbine is used as the input argument.The thermal parameters of the equipment change synchronously through a several-layer nesting cycle.The changing laws of such parameters as the steam consumption of each main piece of equipment,temperature of the steam and water in each heat exchanger,and overall steam consumption and efficiency with respect to the operating conditions are obtained.The reasons for the above-mentioned changing laws are analyzed and the calculation values compared with the design values.[Results]The results show that the margins of error of the system parameters are small,which satisfies calculation accuracy requirements.[Conclusions]The proposed method and changing laws in this paper provide a reference for the study of the parameter matching characteristics of secondary circuit systems.