We give an example of a spacetime having an infinite thin rotating cylindrical shell constituted by a charged perfect fluid as a source. As the interior of the shell the Bonnor–Melvin universe is considered, while its exterior is represented by Datta– Raychaudhuri spacetime. We discuss the energy conditions and we show that our spacetime contains closed timelike curves. Trajectories of charged ...

A Finite-difference method for simulation of sonic waves propagating in a vicinity of a borehole filled with fluid and surrounded by a 3D heterogeneous elastic medium is developed. The method utilizes an explicit second order of approximation FD scheme on staggered grids that approximates the elastodynamic system of equations in cylindrical coordinates. A computational domain is surrounded by a...

We give an example of a spacetime having an infinite thin rotating cylindrical shell constituted by a charged perfect fluid as a source. As the interior of the shell the Bonnor–Melvin universe is considered, while its exterior is represented by Datta– Raychaudhuri spacetime. We discuss the energy conditions and we show that our spacetime contains closed timelike curves. Trajectories of charged ...

We study the lubrication of fluid-immersed soft interfaces and show that elastic deformation couples tangential and normal forces and thus generates lift. We consider materials that deform easily, due to either geometry e.g., a shell or constitutive properties e.g., a gel or a rubber , so that the effects of pressure and temperature on the fluid properties may be neglected. Four different syste...

Structural optimization using computational tools has become a major research field in recent years. The paper deals with a sizing optimization analysis of laminated circular cylindrical shell. For thin-walled shells, the classical shell theory is capable of accurately predicting the shell behavior. The weight minimization subjected to displacement constraint within the numerical optimization o...

in this study, thermo-mechanical nonlinear vibration of a polyethylene (pe) cylindrical shell embedded in an elastic foundation was investigated. the shell is reinforced by armchair carbon nanotubes (cnts) where characteristics of the equivalent composite being determined using mori-tanaka model. the elastic medium is simulated using the spring constant of the winkler-type,  . employing nonline...

It is shown that the dispersive Rayleigh wave propagating around a concave cylindrical surface is substantially less attenuated by fluid loading than the corresponding wave on a flat surface. First, the analytical solution for vertically polarized shear wave scattering from a fluid-filled cylindrical cavity is formulated in the time domain, then the signal of interest is gated out and spectrum ...

The problem of finite amplitude wave propagation in fluid-filled distensible tubes, although of potentially wide general interest in industrial piping systems, finds particularly important application in biomedical circulatory phenomena. Mathematical and laboratory studies of such coupled fluid-shell interactions have led to novel contributions in the field of Biomechanics, an area of continuin...

In this study, discrepancies between the free vibration of fiber-metal laminate (FML) and composite cylindrical shells reinforced by carbon nanotubes (CNTs) based on Love’s first approximation shell theory have been considered by beam modal function model. The representative volume elements consist of three and four phases for composite and FML structures, respectively, which include fiber, CNT...