Creep Analysis of Rotating Thick Cylinders Subjected to External and Internal Pressure: Analytical and Numerical Approach

Abstract

Creep analysis is crucial when dealing with thick rotating cylinders exposed to a steady load or stress at a higher temperature. These cylinders present a fundamental constituent in a variety of dynamic engineering applications, such as pressure vessels, hydraulic cylinders, gun barrels, boilers, fuel tanks, aerospace technologies, nuclear reactors, and military equipment. Thus, severe mechanical and thermal loads cause significant creep and reduce service life. Hence, the prediction of creep in such axisymmetric components, including pressure vessels, subjected to steady load at elevated temperatures is extremely important and quite a complex task. Thus, in this study, the creep behavior in a rotating thick-walled cylinder made of Al-SiCp composite subjected to constant load as well as internal and external pressures is investigated, both analytically and numerically, using FEM. A wide range of rotational speeds effect on the process is also included. The creep behavior is assumed to follow the Norton constitutive model, and for stress failure analysis, von Mises yield criteria are adopted. The effect of internal and external pressures, as well as the rotational speed on the stresses, strains, and strain rates in the cylinder, is studied and presented. Both finite element analysis (FEA) and Lame’s theory were used to determine the radial, tangential, and longitudinal displacements and corresponding stresses, as well as the equivalent Von Mises stresses and strain rate distributions in the cylinder revolving about its own axis. It is observed that with the increase of the internal pressure in the cylinder, the strain rate increases. Meanwhile, when subjecting the cylinder to both external and internal pressures, the strain rates tend to decrease. For instance, it was also found that stress and strain rates were higher for the 1000 rad/sec rotational speed of thick cylinder in comparison with lower rotational speeds of 300 and 500 rad/sec. Also, it is noticed that the variation in these values at the inner radius was more than those found at the outer radius. All results of the stresses, strains, and strain rate distributions obtained are found to be in full agreement with the published data. Furthermore, all plotted results of the stresses, strains, and strain rate distributions obtained through the analytical approach were found to be in exceptional compliance with those solutions obtained using finite element analysis (FEA).