Molecular dynamics modeling of the thermal conductivity of irradiated SiC as a function of cascade overlap

The interaction between the damage state and the thermal conductivity is studied in this paper. The damage propagation and the effective thermal conductivity of the damaged continuum is studied using equilibrium molecular dynamics (EMD) method based on the Green-Kubo relation. A solid gold lattice is considered and the damage is initiated and propagated by stretching two opposite ends while system is maintained at constant volume, constant temperature (NVT) condition. Both Lennard-Jones (LJ) 6–12 and embedded-atom method (EAM) potentials are used to model the inter-atomic interactions. Results are presented illustrating the load-displacement relationship during damage growth and the thermal conductivity change behavior for a selected crack length.

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Molecular Dynamics Modeling of Heat Transport in Metals and Semiconductors

2010 14th International Heat Transfer Conference, Volume 6 ◽

10.1115/ihtc14-23314 ◽

2010 ◽

Author(s):

Sreekant Narumanchi ◽

Kwiseon Kim

Keyword(s):

Experimental Data ◽

Thermal Conductivity ◽

Molecular Dynamics ◽

Thermal Transport ◽

Hybrid Electric Vehicle ◽

Heat Dissipation ◽

Phonon Dispersion ◽

Interfacial Resistance ◽

Dynamics Modeling ◽

Molecular Dynamics Modeling

Interfacial thermal transport is of great importance in a number of practical applications where interfacial resistance between layers is frequently a major bottleneck to effective heat dissipation. For example, efficient heat transfer at silicon/aluminum and silicon/copper interfaces is very critical in power electronics packages used in hybrid electric vehicle applications. It is therefore important to understand the factors that govern and impact thermal transport at semiconductor/metal interfaces. Hence, in this study, we use classical molecular dynamics modeling to understand and study thermal transport in silicon and aluminum, and some preliminary modeling to study thermal transport at the interface between silicon and aluminum. A good match is shown between our modeling results for thermal conductivity in silicon and aluminum and the experimental data. The modeling results from this study also match well with relevant numerical studies in the literature for thermal conductivity. In addition, preliminary modeling results indicate that the interfacial thermal conductance for a perfect silicon/aluminum interface is of the same order as experimental data in the literature as well as diffuse mismatch model results accounting for realistic phonon dispersion curves.

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Molecular Dynamics Modeling of Thermal Conductivity of Engineering Fluids and Its Enhancement Due to Nanoparticle Inclusion

CANEUS2006: MNT for Aerospace Applications ◽

10.1115/caneus2006-11019 ◽

2006 ◽

Author(s):

C. B. Sobhan ◽

Nithin Mathew ◽

Rahul Ratnapal ◽

N. Sankar

Keyword(s):

Thermal Conductivity ◽

Molecular Dynamics ◽

Metallic Nanoparticles ◽

Volume Fraction ◽

Equations Of Motion ◽

Thermal Conductivity Enhancement ◽

Interatomic Potentials ◽

Dynamics Modeling ◽

Conductivity Enhancement ◽

Molecular Dynamics Modeling

A theoretical methodology based on molecular dynamics modeling, for the estimation of the enhancement of the thermal conductivity of fluids by the introduction of suspended metallic nanoparticles is proposed here. This involves the process of generating the atomic trajectories of a system of a finite number of particles by direct integration of the classical Newton’s equations of motion, with appropriate interatomic potentials and application of suitable initial and boundary conditions. Algorithms are made for simulating the nanofluid abiding the procedural steps of the Molecular Dynamics method. The method is presented as a means to solve the generic problem of thermal conductivity enhancement of liquids in the presence of nanoparticles, and illustrated using a specific simulation procedure with properties representing water and platinum nanoparticles. The thermal conductivity enhancement in the base fluid due to suspension of nanoparticles, estimated using Molecular dynamics simulations are compared with existing experimental results and those predicted by conventional effective medium theories. Parametric studies are conducted to obtain the variation of thermal conductivity enhancement with the temperature, and the volume fraction of the nanoparticles in the suspension.

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Molecular Dynamics Modeling of Thermal Conductivity of Silicon/Germanium Nanowires

Фізика і хімія твердого тіла ◽

10.15330/pcss.19.3.222-225 ◽

2019 ◽

Vol 19 (3) ◽

pp. 222-225

Author(s):

A. Kishkar ◽

V. Kurylyuk

Keyword(s):

Thermal Conductivity ◽

Molecular Dynamics ◽

Silicon Germanium ◽

Nonequilibrium Molecular Dynamics ◽

Dynamics Modeling ◽

Si Nanowires ◽

Germanium Nanowires ◽

Molecular Dynamics Modeling ◽

Phonon Spectra ◽

Dynamics Method

The thermal conductivity of silicon/germanium nanowires with different geometry and composition has beenstudied by using the nonequilibrium molecular dynamics method. The thermal conductivity of the Si1-xGexnanowire is shown to firstly decrease, reaches a minimum at x=0.4 and then to increase, as the germaniumcontent x grows. It was found that in the tubular Si nanowires the thermal conductivity decreases monotonouslywith increasing radius of the cylindrical void. The phonon spectra were calculated and the mechanisms of phononscattering in the investigated nanowires were analyzed.

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