Accession Number:

ADA595916

Title:

Scaling Laws and Mesoscopic Modeling of Heat Transfer in Nanofibrous Materials and Composites

Descriptive Note:

Final rept. 30 Sep 2010-30 Sep 2013

Corporate Author:

VIRGINIA UNIV CHARLOTTESVILLE OFFICE OF SPONSORED PROGRAMS

Personal Author(s):

Report Date:

2013-11-26

Pagination or Media Count:

12.0

Abstract:

The structure -- thermal transport properties relationship for nanofibrous materials based on carbon nanotubes CNTs are investigated by performing a multiscale computational study combining atomistic molecular dynamics simulations of heat transfer in small groups of CNTs with mesoscopic modeling of thermal conductivity in CNT-based materials, such as CNT bundles, buckypaper, and vertically-aligned CNT forests. Some of the key results of this study are as follows. 1 General scaling laws governing the heat transfer in nanofibrous network materials with different structural organization are derived analytically and verified in mesoscopic simulations 2 Contrary to the common assumption of the dominant effect of the contact CNT-CNT conductance, the contribution of intrinsic conductivity of CNTs is found to control the value of the effective conductivity of CNT networks at densities and CNT lengths typical for real materials 3 Several distinct regimes of the acoustic energy dissipation are established in atomistic simulations of individual CNTs 4 The dominant role of bending buckling in stabilization of CNT networks is revealed and the contribution of the thermal resistance of buckling kinks to the thermal conductivity of CNT materials is established.

Subject Categories:

  • Refractory Fibers
  • Thermodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE