No abstract

No abstract

Transverse vibration of nickel coated carbon nanotubes is investigated by using molecular dynamics simulations. The simulations are carried out for armchair and zig-zag carbon nanotubes with various lengths. Uncoated and nickel coated carbon nanotubes having same lengths are analyzed and their vibrational behaviors are compared. Free transverse vibrations of nickel coated carbon nanotubes are modelled by using a two-phase local–nonlocal Euler–Bernoulli beam model and solved by finite element method. Nonlocal parameter of the beam model is calibrated based on molecular dynamics simulation results. It is seen that for the same length diameter ratio, the nickel coated carbon nanotubes have similar vibrational characteristics with the uncoated carbon nanotubes but their natural frequencies are smaller than the uncoated ones. Also, it is shown that by using proper nonlocal parameters for each radius length ratio, the two-phase local–nonlocal Euler–Bernoulli beam model can successfully predict the natural frequencies of both short and long nanotubes. Besides natural frequencies and mode shapes, the clustering of nickel atoms depend on simulation temperature which is discussed during oscillation of nickel coated carbon nanotubes.

No abstract

A novel method for production of variable stiffness woven fabrics with curved advanced fibers is presented. A scalable concept design is introduced. Several variable stiffness fabrics are woven by the prototype loom. The weaving process and woven fabrics are examined. Two distinct regions of the fabric which are showing different behaviors are observed. Based on the two regions identified the curved fibers of the woven fabric are simplified and modeled as a three-dimensional unit mesh. Geometry variation of the curved fibers and stiffness variation of the woven fabrics are discussed for these two distinct regions by using the developed model.