堆芯功率变化对燃料包壳表面污垢沉积行为的影响研究  

Effect of core power variation on crud deposition behavior on fuel cladding surface

作　　者：廖家鹏 叶杰 金德升 商超皓 胡友森 LIAO Jiapeng;YE Jie;JIN Desheng;SHANG Chaohao;HU Yousen(China Nuclear Power Technology Research Institute Co.,Ltd.,Shenzhen 518000,China)

机构地区：[1]中广核研究院有限公司,深圳518000

出　　处：《核技术》2022年第8期99-104,共6页Nuclear Techniques

基　　金：中国博士后科学基金(No.2021M703023)资助。

摘　　要：压水堆一回路腐蚀产物流经堆芯时,在燃料包壳表面过冷泡核沸腾的作用下在燃料包壳表面沉积产生堆芯燃料污垢,燃料污垢的沉积行为受一回路腐蚀产物浓度和堆芯沸腾率的影响。本研究从反应堆堆芯功率变化对一回路腐蚀产物浓度和堆芯沸腾率的影响角度出发,采用自主污垢行为分析软件CAMPSIS进行评估计算,揭示堆芯功率变化对燃料包壳表面污垢沉积质量和最大污垢厚度的影响规律。结果表明:在75%~100%满功率(Full Power,FP)范围内,反应堆运行至相同日历天,受堆芯沸腾率和腐蚀产物浓度综合作用的影响,堆芯功率越低,循环末期堆芯污垢质量越小,但堆芯最大污垢厚度越大。当堆芯功率降低至50%FP时,堆芯最大沸腾率接近零,循环末期的堆芯污垢质量和堆芯最大污垢厚度均最小。[Background] For a pressurized water reactor(PWR), under the synthesis effects of primary water chemistry, reactor operation mode, system facilities replacement, fuel design and management, the corrosion products in primary coolant will deposit on the outer surface of fuel cladding, which is commonly called fuel crud. Fuel crud formed on the cladding surface may result in crud induced localized corrosion(CILC), crud induced power shift(CIPS) and raise the primary source term. The deposition behavior of fuel crud is affected by both the corrosion products concentration and the core boiling rate. [Purpose] This study aims to investigate the influences of core power variation on the corrosion products concentration and the core boiling rate, and eventually evaluate the fuel crud deposition states under different core powers. [Methods] The core crud mass and the maximum crud thickness on fuel cladding surface were estimated by the CAMPSIS, an independent crud behavior analysis software developed by China Nuclear Power Technology Research Institute Co., Ltd(CNPRI). Influence of core power variation and the combined effect of core boiling rate and corrosion product concentration were analyzed. [Results] Computational results that, within the range of 75%~100% full power(FP), the lower the core power is, the smaller the core crud mass will be, but the maximum crud thickness will increase. When the core power decreases to 50% FP, the maximum boiling rate is close to zero, and both of the core crud mass and the maximum crud thickness are minimum.[Conclusions] The core power reduction of a nuclear reactor may lead to the increase of local fuel crud thickness,and adversely affect the heat transfer between the fuel cladding and the coolant. It is suggested that the influence of core power reduction on fuel crud deposition should be considered if a nuclear reactor tends to operate at a lower core power.

关 键 词：压水堆核电站 燃料包壳 堆芯功率 燃料污垢 

分 类 号：TL382[核科学技术—核技术及应用]