LOCA条件下包壳材料感应和电阻加热温升行为的对比研究

Comparative Study on the Temperature Rise of the Cladding Material during Induction and Resistance Heating under LOCA Condition

目的使有限元模拟技术成为一种切实有效的研究方法,进而为高性能反应堆包壳材料的设计以及可能发生的LOCA(Loss of Coolant Accident)事故下的应急措施等提供理论依据。方法基于COMSOL软件模拟分析典型锆合金核材料在LOCA条件下分别经感应加热和电阻加热后的温升行为。结果感应加热条件下,锆材的体积内最高温度、体积平均温度与表面中心点温度的差值随着温度上升逐渐增大,在1200℃瞬时温度下,温度差值最高,约为41℃。电阻加热条件下,锆材的体积内最高温度、体积内中心温度与表面中心点温度在加热的整个阶段近乎重合,最大差值约为3℃;锆材的体积平均温度、表面平均温度与表面中心点温度的差值出现负值,最大差值约为30℃。结论电阻加热和感应加热虽均适用于堆外研究反应堆失水事故下包壳材料所面临的超高温度及超快升温速率的工况模拟,但限于实际工况下电阻加热速率的滞后性,推荐使用感应加热进行后续的模拟研究工作。相关结果可为高性能反应堆包壳材料的设计提供必要的理论依据。

The work aims to enable the finite element simulation technology to become a practical and effective research method, and then provide the theoretical basis for the design of high-performance reactor cladding materials and possible emergency measures under the LOCA(Loss of Coolant Accident). Based on COMSOL software, the temperature rise of typical zirconium alloy nuclear materials after induction heating and resistance heating under LOCA conditions was simulated herein. The results showed that the difference between the highest temperature, the average volume temperature and the surface center temperature increased with the rise of temperature. At transient temperature of 1200 ℃, the temperature difference was the highest, about 41 ℃. Under the condition of resistance heating, the highest temperature in volume, the center temperature in volume and the surface center temperature of the zirconium material almost coincided with one another in the whole heating stage, with the maximum difference of about 3 ℃. The difference between the average volume temperature, the average surface temperature and the surface center temperature of zirconium material was negative, and the maximum difference was about 30 ℃. It is found that both resistance heating and induction heating are suitable for the simulation of ultra-high temperature and ultra-fast temperature rise rate for cladding materials under LOCA conditions. However, due to the lag of resistance heating rate under actual working conditions, induction heating is recommended for subsequent simulation experiments. The relevant results can provide necessary theoretical basis for the design of high-performance reactor cladding materials.