The pressure variances in the reactor core and containment of a High Temperature Gas-cooled Reactor (HTGR) after a primary loop pressure boundary break accident determine the structural integrity and safety of the reactor. Based on mass conservation, energy conservation and state equations, explicit formulae for the transient pressure and temperature variances in the pressure vessels were deduced, and a set of differential equations for the transient pressure and temperature variances in the containment were developed. Numerical simulation was also conducted to investigate the transient pressure and temperature variances in the pressure vessels and containment. The results show that energy transformation due to expansion work cannot be neglected. The maximum pressure in the containment could increase by 40 percent due to blockage caused by air in the containment. Detailed numerical simulations of the transient pressure and temperature variance in the reactor core flow passages were also conducted. The results show that the pressures acting on the reactor core and containment are below acceptable values.
研发一种新型蒸汽发生器必须进行一定规模的工程验证试验。清华大学核能与新能源技术研究院在其实验基地建设了高温气冷堆示范工程(HTR-PM)螺旋管式直流蒸汽发生器的工程验证试验回路(engineering test facility for steam generator,ETF-SG)。工程验证试验回路能够模拟HTR-PM运行参数,可对HTR-PM蒸汽发生器一个换热组件进行1∶1的工程验证试验。回路设计热功率10 MW,氦回路设计压力8 MPa,最高设计温度800℃,二回路设计压力18 MPa,最高设计温度600℃。在工程验证试验回路上针对高温气冷堆蒸汽发生器完成了几十项热工水力试验,对蒸汽发生器的温度均匀性、堵管后温度分布及其温度展平调节、热工水力瞬态特性、两相流不稳定性等进行了试验研究,验证了HTR-PM螺旋管式直流蒸汽发生器的热工水力和结构设计,并为其调试、运行、低功率及启停工况参数的确定提供了重要数据和参考。