Jixie qiangdu (Jan 2017)
CONSTRAINT EFFECT ANALYSIS OF THE SEMI-ELLIPTICAL SURFACE CRACK FOR A REACTOR VESSEL SUBJECTED TO PRESSURIZED
Abstract
The specimen is a reactor pressure vessel with a semi-elliptical surface crack with axial orientation and its 3D finite element numerical modeling is built. Based on J-A2 two parameters method,analysis is performed by considering constraint effect,at T = 561 K,p = 10 MPa. Three different aspect ratio( a/c) and Ramberg-Osgood exponent( n) is analylized,namely a/c = 1/2,1/3,1/5( a = 20 mm,c = 40 mm,60 mm,100 mm) and n = 10,15,20. The corresponding J-integral and constraint parameter A2 is gained. The research results show that: J-integral increases with the decrease of aspect ratio a/c,and RambergOsgood exponent( n) almost has no effect on J-integral. The increase of Ramberg-Osgood exponent( n) will weaken the effect of aspect ratio a/c on A2. The most serious point is the deepest point of a crack.