1. After a reactor is shutdown, a considerable amount of sensible (or stored) heat is still present in the fuel rods and heat continues to be generated by the decay of fission products and by fission caused by delayed neutrons.
1. 停堆以后,燃料组件内仍然存在大量的热量,同时裂变产物的衰变和缓发中子引发的剩余裂变还会产生新的热量。
2. The sensible heat and delayed fission heat are removed within about half a minute and then only the decay heat determines the cooling requirements.
2. 存储的能量以及缓发中子的能量在半分钟内就导出了,只有剩余的衰变热的导出取决于冷却系统的能力。
3. The thermal power from this source is initially about 7% of the operating power at shutdown, then decreased to somewhat more than 6% after 1 second, to 1.3% after 1 hour and 0.4% after day.
3. 停堆瞬间的热功率约为7%额定功率,1秒后降至6%,1小时后至1.3%,1天后0.4%。
4. The residual heat removal system also called shutdown cooling system is provided to remove the decay heat from the core to the cold shutdown temperature at controlled rate and maintains this temperature until the plant is started up again.
4. 余热排出系统又称为停堆冷却系统,其主要功能就是以可控速率导出剩余衰变热,直至冷停堆的温度值,并保持此温度直到电厂再次启动。
5. In some nuclear power plants, the residual heat removal system also serves as part of the emergency core cooling system, during the injection and recirculation phase following a Loss of Coolant Accident (LOCA)5. 在某些电厂,在LOCA后的注射和再循环阶段,停冷系统也作为应急堆芯冷却系统的一部分。
6. The residual heat removal system consists of two residual heat exchangers, two residual removal pumps and the associated piping, valves and instrumentation for operational control.
6. 停冷系统有2个停冷热交换器,2台停冷泵以及相关的管道,阀门和仪表组成。
7. The inlet line to the residual heat removal system is connected to the hot leg of one of the reactor coolant loop, while the return lines are connected the cold legs of each of the reactor coolant loops.
7. 停冷系统的吸入口取自一个主管道的热段,回水注入管则与每个主管道的冷段相连。
8. The delay heat is transferred to the component cooling water circulating through the shell side of the residual heat exchangers.
8. 热量的移出是靠停冷热交换器壳侧的设冷水来实现的。
9. The initial phase of reactor cooldown is accomplished by transferring heat from the reactor coolant system to the steam and power conversion system through the steam generator.
9. 停堆初期(第一阶段)的冷却过程:通过蒸汽发生器将反应堆冷却剂系统的能量传输给二次侧的蒸汽。
10. The second phase of cooldown starts with the residual heat removal system being placed in operation approximately four hours after reactor shutdown when the temperature and pressure of the reactor coolant system are approximately 180℃ and 2.94MPa, respectively.
10. 停堆大约4小时以后,当主系统温度和压力分别降至180度个2.94MPa,停冷系统投入运行,用于第二阶段的冷却。
11. Both residual heat removal pumps are utilized during refueling to pump borated water from the refueling water storage tank to the refueling cavity.
11. 换料时,2台停冷泵启动运行,用于将换料水箱的水输送至换料水池。
12. To assure reliability, the two residual heat removal pumps are connected to separate electric buses and each bus is automatically transferred to a separate emergency diesel supply.
12. 为保证可靠性,两台停冷泵分别由两条独立的母线供电,两条母线可以分别自动切换到独立的应急柴油机供电。