three-dimensional fracture analysis of defected tubes under detonation

The main purpose of this article is threedimensional finite element analysis of defected tubes under gas detonation loading. the variation of stress intensity factor through the semi elliptical crack front for different defect profiles versus the simulation time is studied. the structural linear elastic response of tube in presence of an embedded defect is considered. the results show that the traveling pressure loads can affect the distribution of fracture factors along the defect shape. it can be seen that the moving pressure loads lead to occur the mixed mode stress intensity factor in thick walled tubes. the dependency of the stress intensity factors on the crack configuration, time period of loading and typical pressuretime profile is investigated. it can be seen that the schematic of stress/straintime trace profiles strongly dependents on the location of points through the wall thickness. the capability of finite element modeling in analysis of three dimensional dynamic transient problems has been shown.