Loading...

Instability Analysis of Carbon Nanotubes and Graphitic Shells Conveying Fluid

Ramazani Ali-Akbari, Hossein | 2010

778 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 41403 (45)
  4. University: Sharif University of Technology
  5. Department: Aerospace Engineering
  6. Advisor(s): Haddadpour, Hassan
  7. Abstract:
  8. In this research, the instability analysis of single-walled carbon nanotubes (SWCNTs) and graphitic shells conveying fluid is investigated based on the molecular structural mechanics. Using the reduced order models for fluid and structure, the dynamic behavior of carbon nanotubes (CNTs) conveying fluid is accurately modeled via a few number of lowest flow modes and natural frequencies and mode shapes of CNTs structure. In addition, the boundary element method (BEM) is used to model the potential flow. The molecular mechanics (MM) model is applied to modal analysis and driving the natural frequencies and mode shapes of SWCNTs. The effect of chirality on flow-induced instability is taken into account. The results show that the vibrational behavior of SWCNTs conveying fluid is significantly depended on small-scale effect, but, the effect of chirality is negligible. For example the dimensionless divergence velocity of an ordinary clamped-clamped pipe conveying fluid is 6.28, but, for a SWCNT by length of 16 nm is 5.02. Besides, the results are compared with nonlocal beam theory represented in the literature and the suitable values for the nonlocal parameter e_0 a are obtained to adopt this model with MM approach. The results for instability analysis of graphitic shells are compared with classical continuum shell models by consideration of the various wall thicknesses that are represented in literature, and a continuum shell model with equivalent thickness is developed based on the molecular mechanics approach
  9. Keywords:
  10. Carbon Nanotubes ; Reduced Order Model ; Boundary Element Method ; Modal Analysis ; Instability Analysis ; Graphitic Shells

 Digital Object List

 Bookmark

No TOC