MOLECULAR DYNAMICS SIMULATION ON THERMAL CONDUCTIVITY OF ONE DIMENISON NANOMATERIALS

The Non-equilibrium molecular dynamics (NEMD) simulation method which is based on the linear response theory is applied to simulate the thermal conduction process of C, BN and SiC nanotubes. The three-body Tersoff potential is used to simulate the interactions among atoms. The effects of axial length, temperature and tensile strain on the axial thermal conductivity of the three kinds of nanotubes are investigated, and their thermal conductivities are compared and analyzed. The simulation results show that the axial thermal conductivity increases as the axial length increases, and exhibits a relationship k ∝ Lthat is in agreement with the solution of Boltzmann-Peierls phonon transport equation (B-P equation). It is found that the thermal conductivity of nanotube decreases with the increase of temperature. As the tensile strain increases, the thermal conductivity of nanotubes show an slight increase first, and then decreases. But, the corresponding tensile strains at which the tendency of thermal conductivity of the three nanotubes changes are different. Under the same conditions, the sequence of thermal conductivity from the biggest to the smallest is in the order of