Vibrations of circular cylindrical shells made of layered composite materials are considered. The shells are weakened by circumferential cracks. The influence of circumferential cracks with constant depth on the vibration of the shell is prescribed with the aid of a matrix of local flexibility coupled with the coefficient of the stress intensity known in the linear elastic fracture mechanics. N...

The temperature dependence of structural properties for infinitely long gold nanowires is studied. The molecular dynamics simulation method and the embedded-atom potential are used. The wires constructed at T = 0 K with a face-centered cubic structure and oriented along the (111), (110), and (100) directions are investigated. It was found that multiwalled structures form in all these nanowires....

in this paper, the radial breathing mode (rbm) frequencies of multi-walled carbon nanotubes (mwcnts) are  obtained based on the multiple-elastic thin shell model. for this purpose, mwcnt is considered as a multiple concentric elastic thin cylindrical shells, which are coupled through van der waals (vdw) forces between two adjacent tubes. lennard-jones potential is used to calculate the vdw forc...

Coupling coefficients for thin shells of arbitrary curvature based upon a ray-theoretic approach devised by the authors are benchmarked against exact and high-frequency results for canonical geometries, i.e., the spherical nd infinite circular cylindrical shells. The well-known high-frequency approximations of the coupling coefficients are found to describe their magnitude accurately but not th...

The future X-ray observatory missions require grazing-incidence x-ray optics with angular resolution of < 5 arcsec halfpower diameter. The achievable resolution depends ultimately on the quality of polished mandrels from which the shells are replicated. With an aim to fabricate better shells, and reduce the cost/time of mandrel production, a computercontrolled polishing machine is developed for...

Cylindrical shells are principal structural elements that used for many purposes, such as offshore, sub-marine, and airborne structures. The nonlinear mechanics model of internal blast loading was established to predict the dynamic pressure cylindrical shells. However, due complexity mechanical model, solution process is time-consuming. In this study, linearized, solved. First, a subjected prop...

Abstract Cylindrical shell structures are ubiquitous and essential supporting in various engineering applications. The aim of this research work is to provide a comprehensive overview the behavior cylindrical under different loading conditions, including external pressure, axial compression, bending moment. study found that shells was affected by their geometry, diameter, length, thickness, imp...

A mathematical analysis has been carried out for the axial flow of a Bingham plastic fluid, in the Concentric Cylinder Viscometer which consists of a cylindrical sample holder (the cup) and a cylindrical spindle (the bob) coaxial with the cup. The fluid to be tested flows through the annular gap of the cup and the bob system, sheared by the rotation of the inner cylinder, while the outer cy...

Cylindrically symmetric structures such as concentric rings and rosettes arise out of thin polymeric films subjected to strong electric fields. Experiments that formed concentric rings and theory capable of explaining these and other cylindrical structures are presented. These rings represent an additional member of a class of structures, including pillars and holes, formed by electrohydrodynam...