C* Based Life Assessment of 3D Crack at High Temperature

C*에 기초한 3차원 고온균열 수명평가

  • Han, Tae-Soo (Dept.of Mechanical Engineering, Graduate School of Sogang University) ;
  • Yoon, Kee-Bong (Dept.of Mechanical Engineering, Sogang University) ;
  • Lee, Hyung-Il (Dept.of Mechanical Engineering, Chungang University)
  • 한태수 (서강대학교 대학원 기계공학과) ;
  • 윤기봉 (중앙대학교 기계공학부) ;
  • 이형일 (서강대학교 기계공학과기계공학부)
  • Published : 2001.05.01


In recent years, the subject of remaining life assessment has drawn considerable attention in chemical plants, where various structural components typically operate at high temperature an pressure. Thus a life prediction methodology accounting for high temperature creep fracture is increasingly needed for the components. Critical defects in such structures are generally found in the form of semi-elliptical surface crack, and the analysis of which is consequently an important problem in engineering fracture mechanics. On this background, we first develop an auto mesh generation program for detailed 3-D finite element analyses of axial and circumferential semi-elliptical surface cracks in a piping system. A high temperature creep fracture parameter C-integral is obtained from the finite element analyses of generated 3-D models. Post crack growth module is further appended here to calculate the amount of crack growth. Finally the remaining lives of surface cracked pipes for various analytical parameters are assessed using the developed life assessment program.


Semi-elliptical Surface Crack;C*-integral;Life Assessment Program;Auto Mesh Generation Program;Paris-law-type Crack Growth


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