Reliable Fracture Analysis of OF 2-D Crack Problems Using NI-MVCCI Technique

Abstract

A posteriori error estimation and adaptive refinement technique for 2-D/3-D crack problems is the state-of-the-art. In this paper a new a posteriori error estimator based on strain energy release rate (SERR) or stress intensity factor (SIF) at the crack tip region has been proposed and used along with the stress based er- ror estimator for reliable fracture analysis of 2-D crack problems. The proposed a posteriori error estimator is called the K-S error estimator. Further, h-adaptive mesh refinement strategy which can be used with K-S error estimator has been proposed for fracture analysis of 2- D crack problems. The performance of the proposed a posteriori error estimator and the h-adaptive refinement strategy have been demonstrated by employing 4-noded, 8-noded and 9-noded plane stress finite elements. The proposed error estimator together with the h-adaptive re- finement strategy will facilitate automation of fracture analysis process to provide reliable solutions. keyword: Finite element method; Fracture analysis; Error estimation; Adaptive refinements. can also be used to improve and optimize the structural design. This is based on theassumptionthat the structure is correctly modelled, the environmental conditions are properly defined and FEM software itself performs cor- rectly. The quality of finite element (FE) formulations and FE mesh/idealization employed in FEA will have a direct effect on the solution time, cost, accuracy and reliability of the results. Further, FEA of any practical structure involves large amount of data to be prepared to represent the physical structure. This gives scope for errors in input and inefficient modelling. Therefore, ef- ficient/appropriate use of any software based on FEM, commercial or otherwise, requires basic knowledge of the method and also about the software. As a result, the use of software has been mainly restricted to profession- als, trained analysts and those who are knowledgeable in this field.