Several theoretical and experimental methods for predicting the thermal conductivity
of thin dielectric ¯lms and carbon nanotubes are presented based on two schools of
thought: (1) the physics of the Boltzmann Transport Equation (BTE), and (2) Molec-
ular Dynamics (MD) simulations. First, in relation to models based on the BTE, this
thesis highlights temporal and spatial scale issues by looking at a uni¯ed theory that
bridges physical aspects presented in the Fourier and Cattaneo models. This newly
developed uni¯ed model is the so called C- and F-Processes heat conduction model.
The model introduces the dimensionless heat conduction model number which is the
ratio of thermal conductivity of the fast heat carrier F-Processes to the total thermal
conductivity comprised of both fast F-processes and slow heat carrier C-processes.
Prior work has claimed that macroscopic heat transfer models cannot explain mi-
croscale heat transfer. First, this dissertation provides arguments by showing how
the C-F model is able to extend the use of \macroscopic" constitutive relations for
the prediction of thermal conductivity at the \microscopic" level for thin ¯lms, mul-
tilayer structures, and includes both dielectrics and metals. Second, the in°uence
of external mechanical strain on the thermal conductivity of single-wall carbon nan-
otubes is studied using direct molecular dynamics simulations with Terso®-Brenner
potential for C-C interactions. Three types of external mechanical strain, namely,
axial compression, tension, and torsion are studied. In all three cases, the thermal
conductivity does not degrade much, i.e., it remains within 10% of the pristine nan-
otube values for lower applied strain below the values required for structural collapse.
At higher applied strain, structural collapse occurs, and major reductions in the ob-
served thermal conductivity for axially compressed and torsionally twisted tubes are
University of Minnesota Ph.D. dissertation. December 2008. Major: Mechanical engineering. Advisor: Kumar K. Tamma. 1 computer file (PDF); iii, 281 pages. Includes illustrations.
Anderson, Christianne Vanessa Duim Riberiro.
Thermal heat transport characterization for macroscale, microscale, and nanoscale heat conduction.
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