Digital Repository, ICF12, Ottawa 2009

Font Size: 
Thermal Conductivity of the Damaged Gold Nanowires
Navin Kumar, Kishore Pochiraju

Last modified: 2012-10-03


The damage propagation and the thermal conductivity of a gold nanowire are studied usingmolecular dynamics methods. The frequency spectra of stresses in the wire are also investigatedfor persistent features that correlate with bulk material behavior. The material is modeled usingatomic scale representative volume elements with a finite dimension along one dimension andinfinite dimensions in two others. The initial state temperature, pressure and volume states forthe material are determined using a slow and sequential equilibrium procedure that produces aconvergent energy and stress states. Finite size cracks surfaces are artificially created and thechanges in the dynamic stress states are observed. The frequencies of the dominant modes andthe amplitude of the stress at these modes are described. The shift in the frequency of the lowestdominant mode due to cracking and the increase in the concentration show some of the persistentfeatures expected in the stress state due to the presence of a crack. At selected load steps thewire is mechanically equilibriated and thermal conductivity is measured. In order to measure thethermal conductivity a temperature gradient is established across a simulation domain by addingheat to one group of atoms (hot reservoir) and subtracting heat from another group of atoms(cold reservoir). Results are presented illustrats the thermal conductivity change behavior for aselected crack lengths.

Full Text: PDF