In this paper, simulation and analysis of thin steel cylindrical shells with elliptical cutouts under oblique loading were studied using finite element method. First, the numerical results were validated by the results of experimental test performed by an INSTRON 8802 servo hydraulic machine. Also, the effect of cutout angle (θ), cutout size, cutout position (L0/L) and cutout aspect ratios (b/a...

Thin shells are found in nature at scales ranging from viruses to hens' eggs; the stiffness of such shells is essential for their function. We present the results of numerical simulations and theoretical analyses for the indentation of ellipsoidal and cylindrical elastic shells, considering both pressurized and unpressurized shells. We provide a theoretical foundation for the experimental findi...

Pollen grain and spore shells are natural microcapsules designed to protect the genetic material of the plant from external damage. The shell is made up of two layers, the inner layer (intine), made largely of cellulose, and the outer layer (exine), composed mainly of sporopollenin. The relative proportion of each varies according to the plant species. The structure of sporopollenin has not bee...

Highly stable organic solids, based on van der Waals interactions between cylindrical porphyrinwires, exhibit unique square iodine-channels (10 × 10 Å) and exceptionally hollow porphyrinwires. The functionalized iodine-cavities could be capable of conferring specific adsorption behavior for mercury and lead ions, whereas hollow porphyrinwires might serve as a model for the development of hybrid...

Incorporation of aromatic motifs into the nanosized shells of hollow carbon nitride nanospheres has been reported to develop functional photosynthetic structures for solar energy application. This modification results in an extended π-conjugation system, red-shift of the optical absorption, and an improved charge separation in the shell, while still retaining the unique hollow polymeric nanoarc...

in this research, softening and ratcheting behaviors of ck20 alloy steel cylindrical shells were studied under displacement-control and force-control cyclic axial loading and the behavior of hysteresis curves of specimens was also investigated. experimental tests were performed by a servo-hydraulic instron 8802 machine. the mechanical properties of specimens were determined according to astm e8...

Multi-layer orthotropic finite cylindrical shells with a viscoelastic core in contact with fluids are gaining increasing importance in engineering. Vibrational control of these structures is essential at higher modes. In this study, an extended version of the wave propagation approach using first-order shear deformation theory of shell motion is employed to examine the free vibration of damped ...

Thin cylindrical shell structures can show interesting bistable behaviour. If made unstressed from isotropic materials they are only stable in the initial configuration, but if made from fibre-reinforced composites they may also have a second, stable configuration. If the layup of the composite is antisymmetric, this alternative stable configuration forms a tight coil; if the layup is symmetric...

The study of the stress distribution on a hollow cylindrical fiber placed in a composite material is considered in this work and an analytical solution for this stress distribution has been constructed. Finally some parameters such as fiber’s thickness and fiber’s length are considered and their effects on the distribution of stress have been investigated. For finding the governing relations, c...

We point out the similarities and differences between cylindrical and disk photonic shells separating regions of flat spacetime. PACS numbers: 04.20.-q , 04.20.Jb, 04.40.-b