A modified method to predict failure pressure of steam generator tubes with through wall cracks

Multiple axial cracks in the stream generator tubes is often found. An assessment method of such multiple axial cracks is important for safe operation of plant components. However, assessment method of multiple cracks is no yet well established due to the fact that plastic failure behavior can be very complex. One efficient way to predict plastic behavior is to perform FE damage analyses. This paper proposes a new numerical method to predict ductile failure behavior of steam generator tubes with multiple through wall cracks. In this new method based on the former method, ductile failure criterion was assumed to be a function of the finite element size. To validate the new method, simulated results are compared with experiment results of Alloy 600 thin plates and tubes with through wall cracks