The present work deals with the development of a finite element methodology for obtaining the stress distributions in thick cylindrical HK40 stainless steel pipe that carries high-temperature fluids. The material properties and loading were assumed to be random variables. Thermal stresses that are generated along radial, axial, and tangential directions are generally computed using very complex analytical expressions. To circumvent such an issue, probability theory and mathematical statistics have been applied to many engineering problems, which allows determination of the safety both quantitatively and objectively based on the concepts of reliability. Monte Carlo simulation methodology is used to study the probabilistic characteristics of thermal stresses, and was implemented to estimate the probabilistic distributions of stresses against the variations arising due to material properties and load. A 2-D probabilistic finite element code was developed in MATLAB, and the deterministic solution was compared with ABAQUS solutions. The values of stresses obtained from the variation of elastic modulus were found to be low compared to the case where the load alone was varying. The probability of failure of the pipe structure was predicted against the variations in internal pressure and thermal gradient. These finite element framework developments are useful for the life estimation of piping structures in high-temperature applications and for the subsequent quantification of the uncertainties in loading and material properties.

Shell structures are susceptible to various types of imperfections and damage such as cracking, corrosion, chemical attack and time-dependent material degradation, which may impair their structural integrity and affect their service life. The effects of cracks are important considerations in the design of cylindrical shell structures as they influence on load carrying capacity and safety. This present work is a finite element investigation on the vibration, buckling and fracture analysis of a cracked cylindrical shell subjected to a time varying rotating speed. The effects of crack length, orientation of crack and length-diameter ratio of the cylindrical shell are investigated under free-vibration and buckling. The fracture parameters like stress intensity factor and J-integral of the cracked shell are also studied considering the influence of crack length and crack orientation. Results reveal that the crack length and crack orientation can affect the vibration, buckling behaviour of the cylindrical shell significantly.

The present work deals with the development of finite element methodology for obtaining the stress distributions in thick cylindrical HK40 stainless steel pipe that carry high temperature fluids. The material properties and loading are assumed to be random variables. Thermal stresses that are generated along radial, axial and tangential directions are computed generally using analytical expressions which are very complex. To circumvent such an issue, the probability theory and mathematical statistics have been applied to many engineering problems which allows to determine the safety both quantitatively and objectively based on the concepts of reliability. Monte Carlo simulation methodology is used to study the probabilistic characteristics of thermal stresses which is used for estimating the probabilistic distributions of stresses against the variations arising due to material properties and load. A 2-D Probabilistic finite element code is developed in MATLAB and the deterministic solution is compared with ABAQUS solutions.  The values of stresses that are obtained from the variation of elastic modulus are found to be low as compared to the case where the load alone is varying. The probability of failure of the pipe structure is predicted against the variations in internal pressure and thermal gradient. These finite element framework developments are useful for the life estimation of piping structures in high temperature applications and subsequently quantifying the uncertainties in loading and material properties.

Shell structures are susceptible to various types of imperfections and damage such as cracking, corrosion, chemical attack and time-dependent material degradation, which may impair their structural integrity and affect their service life. The effects of cracks are important considerations in the design of cylindrical shell structures as they influence on load carrying capacity and safety. This present work is a finite element investigation on the vibration, buckling and fracture analysis of a cracked cylindrical shell subjected to a time varying rotating speed. The effects of crack length, orientation of crack and length-diameter ratio of the cylindrical shell are investigated under free-vibration and buckling. The fracture parameters like stress intensity factor and J-integral of the cracked shell are also studied considering the influence of crack length and crack orientation. Results reveal that the crack length and crack orientation can affect the vibration, buckling behaviour of the cylindrical shell significantly.