CAJ | 학술논문

第三代核电厂是国际上最新型的核电厂,设计上均加强非能动冷却机制的应用。非能动自然对流冷却技术在AP1000核电厂非能动堆芯冷却系统、非能动安全壳冷却系统以及ESBWR反应堆中均有应用。本文结合热工水力分析程序 RELAP5/MOD3??3,建立自然对流回路模型,利用流体力学推导自然对流计算,同时分别比较验证轻水、氦气以及水的两相流等多种流体的 RELAP5自然对流计算能力。结果分析显示自然对流能力随冷热源高度差以及流体冷热温差的增大而增大；通过与解析结果的比较发现,RELAP5能很好地模拟自然对流现象。在环路流体为单相水和两相水时,RELAP5模拟结果与解析结果基本一致,两种表征参数误差均能控制在5％左右；当环路流体为氦气时,RELAP5模拟误差稍大。
제삼대핵전엄시국제상최신형적핵전엄,설계상균가강비능동냉각궤제적응용。비능동자연대류냉각기술재AP1000핵전엄비능동퇴심냉각계통、비능동안전각냉각계통이급ESBWR반응퇴중균유응용。본문결합열공수력분석정서 RELAP5/MOD3??3,건립자연대류회로모형,이용류체역학추도자연대류계산,동시분별비교험증경수、양기이급수적량상류등다충류체적 RELAP5자연대류계산능력。결과분석현시자연대류능력수랭열원고도차이급류체랭열온차적증대이증대；통과여해석결과적비교발현,RELAP5능흔호지모의자연대류현상。재배로류체위단상수화량상수시,RELAP5모의결과여해석결과기본일치,량충표정삼수오차균능공제재5％좌우；당배로류체위양기시,RELAP5모의오차초대。
The third-generation nuclear power plant is the latest nuclear power plant, whose application of passive cooling system has been strengthened.Passive natural convection cooling has been typically applied in the passive core cooling system and the passive containment cooling system of AP1000 reactors,and in the ESBWR reactors.Using fluid dynamics formulas and the RELAP5 code, a simple model of natural circulation loop of nuclear reactor has been established to estimate the RELAP5 natural convection calculation capability of light-water,helium and two-phase flow.The results show that the capability of natural convection is strengthened with the increase of the thermal center difference between hot and cold sources and the increases of temperature difference between the hot and cold working fluid.RELAP5 could perform natural convection calculation very well when the fluid is single water or two-phase water,in which,the errors between RELAP5 and analytical results are below 5%.When circulation fluid is helium,the error is larger than the forgoing two kinds of fluid.