基于扩散方程的包壳氧化模型  

A Cladding Oxidation Model Based on Diffusion Equations

作　　者：何晓强[1] 余红星[1] 李锋[1] 江光明[1] 

机构地区：[1]中国核动力研究设计院核反应堆系统设计技术重点实验室,成都610041

出　　处：《核动力工程》2012年第4期44-49,共6页Nuclear Power Engineering

摘　　要：在轻水堆的严重事故中,堆芯中锆包壳与水蒸汽的氧化反应对事故进程的影响至关重要。当氧化时间较长,或者包壳表面水蒸汽流量很小时,基于实验结果的抛物线型公式存在着不足,影响对包壳失效、氢气产生量以及温度的预测。本研究从菲克定律出发,建立以扩散方程为出发点、温度范围宽广的包壳氧化模型。该模型的适用范围比抛物线型公式广,且不受抛物线型公式中假设氧化时间较短和堆芯中水蒸汽流量足够的限制,能很好地模拟长期氧化实验和水蒸汽流量很小时的氧化。另外,该模型能给出包壳中的氧原子分布,为精细模拟包壳脆化失效等现象以及发展先进的包壳失效准则提供条件。During severe accident in PWRs, the cladding oxidation with steam in the core is very important to the accident process. When oxidation time is long, or oxidation occurs in steam starvation conditions, the parabolic rate correlations based on experiments are restricted, which impacts the prediction of cladding failure, hydrogen production, and temperature. According to Fick＇s laws, a cladding oxidation model in a wide temperature range based on diffusion equations is developed. The developed oxidation model has a wider applicability than those parabolic rate correlations, and can simulate long-term experiments well. The restricted assumptions of short-term oxidation time and enough steam environment in the core implemented by those parabolic rate correlations are removed in the model, therefore this model perfectly fit for long-term and steam starvation conditions which are more realistic during a severe accident. This model also can obtaindetailed oxygen distribution in the cladding, which is helpful to simulate the cladding failure in detail and develop advanced cladding failure criteria.

关 键 词：严重事故 包壳 氧化 扩散方程 

分 类 号：TL375[核科学技术—核技术及应用]