高温气冷堆堆芯主动冷却过程动态分析

高温气冷堆紧急停堆后需要快速冷却堆芯，使其达到重新启动条件，制定合理的冷却方案对于减少电厂运行成本和保护设备安全具有重要意义。本文建立了冷却系统的数学模型，对冷却过程中关键设备的传热传质过程进行了动态数值模拟。首先分析了德国高温气冷堆采用的直接冷却方案，结果表明，此方案无法避免对设备形成冷冲击或热冲击，风险性较大。进而提出了适用于我国高温气冷堆的新方案，新方案包括4个步骤：蒸汽发生器排水-卸压-预冷-冷却堆芯。动态分析表明，新方案成功地避免了冷/热冲击，大幅提高了安全性，冷却时间也在可接受范围内。

Transient Analysis of Active Cooling Procedure of HTR Reactor Core

It is crucial to design a proper cooling strategy for the high temperature gas-cooled reactor (HTR) reactor core after the HTR emergency shutdown in order to achieve safety and efficiency and prepare for the restart. A numerical model was set up for the transient simulation of heat and mass transfer during cooling process. Firstly the direct cooling strategy used in thorium high-temperature nuclear reactor (THTR) was analyzed and the results show that this strategy is too risky because of the inevitable hot or cold shock introduced to the equipment. Then a new strategy was presented, which is suitable to Chinese high temperature gas-cooled reactor and includes four steps: Discharging the steam generator, depressurizing, pre-cooling, and cooling the core. The transient simulations show that this new strategy is safer than the direct cooling strategy, by eliminating the hot and cold shock. Meanwhile the time consumed by the cooling process using the new strategy is acceptable.