Abstract Stiffened shells and plates are widely used in engineering. Their performance is highly influenced by the arrangement, or layout, of stiffeners on base shell plate geometric features, topology, these stiffeners. Moreover, modular design beneficial, since it allows for increased quality control mass production. In this work, a method developed that simultaneously optimizes topology thei...

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A knock-down factor is commonly used to take into account the obvious decline of the buckling load in a cylindrical shell caused by the inevitable imperfections. In 1968, NASA guideline SP-8007 gave knock-down factors which rely on a lower-bound curve taken from experimental data. Recent research has indicated that the NASA knock-down factors are inclined to produce very conservative estimation...

In this study, the free vibration of partially fluid-filled laminated composite circular cylindrical shell with arbitrary boundary conditions has been investigated by using Rayleigh-Ritz method. The analysis has been carried out with strain-displacement relations based on Love’s thin shell theory and the contained fluid is assumed irrotational, incompressible and inviscid. After determining the...

Initial results of an investigation towards finding an efficient non-cylindrical fuselage configuration for a conceptual blended-wing-body flight vehicle were presented. A simplified 2-D beam column analysis and optimization was performed first. Then a set of detailed finite element models of deep sandwich panel and ribbed shell construction concepts were analyzed and optimized. Generally these...

abstract: the present study deals with the buckling analysis of the laminated composite truncated conical sandwich shells with flexible core subjected to combined axial compressive load and external pressure. higher order governing equations of the motion are presented for conical composite sandwich shells, where they are derived from the hamilton principle. then, by the use of improved higher-...

Using  principle  of  minimum  total  potential  energy  approach  in conjunction  with  Rayleigh-Ritz  method,  the  electro-thermo- mechanical  axial  buckling  behavior  of  piezoelectric  polymeric cylindrical  shell  reinforced  with  double-walled  boron-nitride nanotube  (DWBNNT)  is  investigated. Coupling  between  electrical and mechanical  fields  are  considered  according  to  ...