CAJ | 학술논문

在压水堆核电站余热排出系统冷热水混合区管道发现了由热疲劳导致的不同方向的浅裂纹群，疲劳裂纹的萌生方向可根据临界面方向进行预测。本文对临界面方向进行了理论推导，得出了双轴疲劳载荷作用下临界面方向的解析解。基于C＋＋语言开发了临界面方向的分析程序，同时采用C＋＋开发的分析程序和有限元软件Code＿Aster计算了临界面方向，并将计算结果与理论解析解进行了对比验证。临界面方向分析结果与余热排出系统管道中发现的热疲劳裂纹方向吻合。研究表明，余热排出系统管道焊接残余应力对热疲劳裂纹萌生方向具有决定性的作用。
재압수퇴핵전참여열배출계통랭열수혼합구관도발현료유열피로도치적불동방향적천렬문군，피로렬문적맹생방향가근거림계면방향진행예측。본문대림계면방향진행료이론추도，득출료쌍축피로재하작용하림계면방향적해석해。기우C＋＋어언개발료림계면방향적분석정서，동시채용C＋＋개발적분석정서화유한원연건Code＿Aster계산료림계면방향，병장계산결과여이론해석해진행료대비험증。림계면방향분석결과여여열배출계통관도중발현적열피로렬문방향문합。연구표명，여열배출계통관도한접잔여응력대열피로렬문맹생방향구유결정성적작용。
A network of multidirectional shallow cracks due to thermal fatigue was dis‐covered in the mixing zone of hot and cold water in the pipe of residual heat removal systems in pressurized water reactors . The fatigue crack initiation direction can be predicted by the critical plane orientation .In this paper ,the theoretical derivation was performed and the analytical solution of the critical plane orientation under biaxial fatigue loadings was obtained .A program based on C+ + language was developed .The computational results of the critical plane orientation using both the C+ + programmed analysis code and the finite element software Code_Aster were compared and validated by the analytical solution .The critical plane orientation is consistent with the observed thermal fatigue crack direction .It is concluded that the thermal fatigue crack direction is determined by the weld residual stress in the pipe of residual heat removal system .