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 ...

The counter roller spinning process is an effective method to form large thin-walled cylindrical parts. By using the internal instead of core mould, may solve problem high cost mould and failure forming large-sized In order study mechanism break through its precision control technology, finite element used analyse effect pass thinning ratio, feed rates, angle inter fillet radius on roundness, s...

The natural frequencies and vibration modes of tank's protective capacitance with welded joints defects under axial static load are determined in order to construct a diagnostic model monitor the propagation. Computer simulation dynamic behavior using computer finite element analysis system NASTRAN was performed. design form cylindrical thin-walled shell allowance for belts from weld rolled she...

In this study a vibration analysis was performed of an isotropic cylindrical shell submerged in fluid, resting on Winkler and Pasternak elastic foundations for simply supported boundary condition. Love’s thin theory exploited strain- curvature- displacement relationship. Shell problem solved by using wave propagation approach. Influence fluid as well were studied the natural frequencies shells....

In various fields of engineering, such structural elements are widely used that, from the point view their strength calculation, can be referred to thin shells (tanks, reservoirs, cylinders, etc.). When calculating thin-walled shells, a number hypotheses adopted simplify solution problem. The problem is most simply solved within framework momentless theory according which only force normal sect...

The implosion of cylindrical shell structures in a high-pressure water environment is studied experimentally. The shell structures are made from thin-walled aluminium and brass tubes with circular cross sections and internal clearance-fit aluminium end caps. The structures are filled with air at atmospheric pressure. The implosions are created in a high-pressure tank with a nominal internal dia...