Richa Sharma

Safety Analysis Using Lebesgue Strain Measure of Thick-Walled Cylinder for Functionally Graded Material under Internal and External Pressure

Safety analysis has been done for thick-walled circular cylinder under internal and external pressure using transition theory which is based on the concept of generalized principal Lebesgue strain measure. Results have been analyzed theoretically and discussed numerically. From the analysis, it can be concluded that circular cylinder made of functionally graded material is on the safer side of the design as compared to homogeneous cylinder with internal and external pressure, which leads to the idea of “stress saving” that minimizes the possibility of fracture of cylinder.

Safety analysis of thermal creep non-homogeneous thick-walled circular cylinder under internal and external pressure using Lebesgue strain measure

Purpose – Safety analysis has been done for thermal non-homogeneous thick-walled circular cylinder under internal and external pressure. The paper aims to discuss these issues. Design/methodology/approach – Transition theory based on the concept of generalized principal Lebesgue strain measure has been used which simplifies the constitutive equations by prescribing a priory the order of the measure of deformation and helps to achieve better agreement between the theoretical and experimental results. Findings – From the analysis, the paper can conclude that by introducing a suitably chosen temperature gradient, non-homogeneous compressible circular cylinder with internal and external pressure for non-linear measure is on the safer side of the design as compared to the cylinder without temperature because circumferential stresses are less for cylinder with temperature as compared to cylinder without temperature. Practical implications – Introduction of temperature gradient leads to the idea of “Stress Savin...

Collapse pressure analysis of transversely isotropic thick-walled cylinder using Lebesgue strain measure and transition theory.

The objective of this paper is to provide guidance for the design of the thick-walled cylinder made up of transversely isotropic material so that collapse of cylinder due to influence of internal and external pressure can be avoided. The concept of transition theory based on Lebesgue strain measure has been used to simplify the constitutive equations. Results have been analyzed theoretically and discussed numerically. From this analysis, it has been concluded that, under the influence of internal and external pressure, circular cylinder made up of transversely isotropic material (beryl) is on the safer side of the design as compared to the cylinders made up of isotropic material (steel). This is because of the reason that percentage increase in effective pressure required for initial yielding to become fully plastic is high for beryl as compared to steel which leads to the idea of “stress saving” that reduces the possibility of collapse of thick-walled cylinder due to internal and external pressure.

Creep deformation of a non-homogeneous thin rotating disk of exponentially varying thickness with internal pressure

In this paper, the creep stresses – radial and circumferential have been obtained for a thin disk rotating with a fixed angular speed. The thickness of the disk decreases radially from inner to outer where as the compressibility increases radially. The disk is axis-symmetric and is in a state of plane stress. It has been observed that variation in thickness and compressibility has significant effects on the stresses for an annular disk. It has been concluded from the discussion that circumferential creep stresses for highly non-homogeneous disk are at the lower side as compared to the circumferential creep stresses for homogeneous disk which leads to the result that highly non-homogeneous disk is better choice for the designing purpose as compared to homogeneous disk.

Finite deformations of functionally graded shell under outer pressure with steady state temperature

In this paper, finite elastic and plastic stresses have been determined for functionally graded shell using the concepts of transition theory and generalized measure of strain i.e. nonlinear terms in the displacements are also considered while in classical theory only infinitesimal strain theory concept has been applied. In this problem of spherical shell, temperature has been applied at the internal surface while pressure is considered to be applied at the external surface. From the detailed analysis, it has been noticed that temperature and pressure have significant effects on functionally graded shell. In this paper, it is found that external pressure required for the fully plastic state from initial yielding is on the higher side for the shell made up of highly functionally graded material as compared to the shell made up of less functionally graded material.In this paper, finite elastic and plastic stresses have been determined for functionally graded shell using the concepts of transition theory and generalized measure of strain i.e. nonlinear terms in the displacements are also considered while in classical theory only infinitesimal strain theory concept has been applied. In this problem of spherical shell, temperature has been applied at the internal surface while pressure is considered to be applied at the external surface. From the detailed analysis, it has been noticed that temperature and pressure have significant effects on functionally graded shell. In this paper, it is found that external pressure required for the fully plastic state from initial yielding is on the higher side for the shell made up of highly functionally graded material as compared to the shell made up of less functionally graded material.

Finite deformations in pressurized thick-walled circular cylinder with steady state temperature

In this paper finite elastic and plastic stresses have been investigated using the concept of transition theory with the use of generalized strain measure i.e. nonlinear terms in the displacement are also included which are not included in classical theory. In this paper, we analyze the impact of temperature and pressure on the circular cylinder which is the cause of failure of cylinder. It has been noticed from the results that pressure and temperature play a significant role in the failure of the cylinder. It has been noticed that cylinder made up of the material whose compressibility is at the higher side is best for the designing purpose as compared to cylinder with less compressible material.