scholarly journals Polarized Thermal Conductivity of Two-Dimensional Dusty Plasmas

2021 ◽  
Author(s):  
Aamir Shahzad ◽  
Madiha Naheed ◽  
Aadil Mahboob ◽  
Muhammad Kashif ◽  
Alina Manzoor ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Molecular Dynamics ◽  
Simulation Method ◽  
Dusty Plasmas ◽  
Two Dimensional ◽  
Strongly Coupled ◽  
External Force Field ◽  
Theoretical Predictions ◽  
System Temperature ◽  
Non Equilibrium Molecular Dynamics

The computation of thermalt properties of dusty plasmas is substantial task in the area of science and technology. The thermal conductivity (λ) has been computed by applying polarization effect through molecular dynamics (MD) simulations of two dimensional (2D) strongly coupled complex dusty plasmas (SCCDPs). The effects of polarization on thermal conductivity have been measured for a wide range of Coulomb coupling (Γ) and Debye screening (κ) parameters using homogeneous non-equilibrium molecular dynamics (HNEMD) method for suitable system sizes. The HNEMD simulation method is employed at constant external force field strength (F*) and varying polarization effects. The algorithm provides precise results with rapid convergence and minute dimension effects. The outcomes have been compared with earlier available simulation results of molecular dynamics, theoretical predictions and experimental results of complex dusty plasma liquids. The calculations show that the kinetic energy of SCCDPS depends upon the system temperature (≡ 1/Г) and it is independent of higher screening parameter. Furthermore, it has shown that the presented HNEMD method has more reliable results than those obtained through earlier known numerical methods.

scholarly journals Molecular Dynamics Simulations on Influence of Defect on Thermal Conductivity of Silicon Nanowires

2021 ◽  
Vol 9 ◽  
Author(s):  
Hao Li ◽  
Qiancheng Rui ◽  
Xiwen Wang ◽  
Wei Yu
Keyword(s):  
Thermal Conductivity ◽  
Molecular Dynamics ◽  
Silicon Nanowires ◽  
Surface Defects ◽  
Low Frequency ◽  
Simulation Method ◽  
Dynamics Simulation ◽  
Non Equilibrium Molecular Dynamics ◽  
Dynamics Simulations ◽  
The Impact

A non-equilibrium molecular dynamics simulation method is conducted to study the thermal conductivity (TC) of silicon nanowires (SiNWs) with different types of defects. The impacts of defect position, porosity, temperature, and length on the TC of SiNWs are analyzed. The numerical results indicate that SiNWs with surface defects have higher TC than SiNWs with inner defects, the TC of SiNWs gradually decreases with the increase of porosity and temperature, and the impact of temperature on the TC of SiNWs with defects is weaker than the impact on the TC of SiNWs with no defects. The TC of SiNWs increases as their length increases. SiNWs with no defects have the highest corresponding frequency of low-frequency peaks of phonon density of states; however, when SiNWs have inner defects, the lowest frequency is observed. Under the same porosity, the average phonon participation of SiNWs with surface defects is higher than that of SiNWs with inner defects.

The Influence of Edge Structure on the Thermal Conductivity of Graphene

2009 ◽  
Author(s):  
Kedong Bi ◽  
Yunfei Chen ◽  
Yujuan Wang ◽  
Minhua Chen
Keyword(s):  
Thermal Conductivity ◽  
Molecular Dynamics ◽  
Simulation Method ◽  
Effect Of Temperature ◽  
Edge Structure ◽  
Similar Length ◽  
Simulated Sample ◽  
Simulation Results ◽  
Non Equilibrium Molecular Dynamics ◽  
Armchair Graphene

Non-equilibrium molecular dynamics (NEMD) simulation method is used to investigate the in-plane thermal conductivity of graphene with different structures. The simulation results demonstrate that, as the length of simulated region increasing, the in-plane thermal conductivity of graphene will become larger. Through investigating the influence of width and edge structure on the in-plane thermal conductivity of graphene, it is also found that the thermal conductivity of wider simulated sample is higher than that of the narrower, and with similar length, the in-plane thermal conductivity of armchair graphene is a little higher than that of zigzag one. The effect of temperature on the thermal conductivity of graphene is also studied in this work.

A Molecular Dynamics Study of Thermal Conductivity in Nanocomposites via the Phonon Wave Packet Method

2009 ◽  
Author(s):  
Zhiting Tian ◽  
Sang Kim ◽  
Ying Sun ◽  
Bruce White
Keyword(s):  
Thermal Conductivity ◽  
Molecular Dynamics ◽  
Wave Packet ◽  
Molecular Dynamics Simulations ◽  
Phonon Scattering ◽  
Flow Direction ◽  
Normal Incidence ◽  
Material Interfaces ◽  
Non Equilibrium Molecular Dynamics ◽  
Dynamics Simulations

The phonon wave packet technique is used in conjunction with the molecular dynamics simulations to directly observe phonon scattering at material interfaces. The phonon transmission coefficient of nanocomposites is examined as a function of the defect size, thin film thickness, orientation of interface to the heat flow direction. To generalize the results based on phonons in a narrow frequency range and at normal incidence, the effective thermal conductivity of the same nanocomposite structure is calculated using non-equilibrium molecular dynamics simulations for model nanocomposites formed by two mass-mismatched Ar-like solids and heterogeneous Si-SiCO2 systems. The results are compared with the modified effective medium formulation for nanocomposites.

Thermal conductivity of silicon using reverse non-equilibrium molecular dynamics

2018 ◽  
Vol 123 (20) ◽  
pp. 205104 ◽  
Author(s):  
Mohamed S. El-Genk ◽  
Khaled Talaat ◽  
Benjamin J. Cowen
Keyword(s):  
Thermal Conductivity ◽  
Molecular Dynamics ◽  
Non Equilibrium Molecular Dynamics ◽  
Non Equilibrium

Effects of Stone-Wales Defects on the Thermal Conductivity of Carbon Nanotubes

2012 ◽  
Vol 134 (9) ◽  
Author(s):  
Li Wei ◽  
Feng Yanhui ◽  
Peng Jia ◽  
Zhang Xinxin
Keyword(s):  
Thermal Conductivity ◽  
Carbon Nanotubes ◽  
Molecular Dynamics ◽  
Thermal Resistance ◽  
Ambient Temperature ◽  
Temperature Profile ◽  
Defect Position ◽  
Non Equilibrium Molecular Dynamics ◽  
Increasing Temperature ◽  
Dynamics Method

The thermal conductivity of carbon nanotubes with Stone-Wales (SW) defects was investigated using non-equilibrium molecular dynamics method. The defect effects were analyzed by the temperature profile and local thermal resistance of the nanotubes with one or more SW defects and further compared with perfect tubes. The influences of the defect concentration, the length, the chirality and the radius of tubes and the ambient temperature were studied. It was demonstrated that a sharp jump in the temperature profile occurred at defect position due to a higher local thermal resistance, thus dramatically reducing the thermal conductivity of the nanotube. As the number of SW defects increases, the thermal conductivity decreases. Relative to the chirality, the radius has greater effects on the thermal conductivity of tubes with SW defects. With the similar radius, the thermal conductivity of armchair nanotube is higher than that of zigzag one. The shorter nanotube is more sensitive to the defect than the longer one. Thermal conductivity of the nanotube increases with ambient temperature, reaches a peak, and then decreases with increasing temperature.

Thermal Conductivity Computation of Nanofluids by Equilibrium Molecular Dynamics Simulation: Nanoparticle Loading and Temperature Effect

2007 ◽  
Vol 1022 ◽  
Author(s):  
Suranjan Sarkar ◽  
R. Panneer Selvam
Keyword(s):  
Thermal Conductivity ◽  
Molecular Dynamics ◽  
Molecular Dynamics Simulation ◽  
Effective Thermal Conductivity ◽  
Copper Nanoparticles ◽  
Base Fluid ◽  
Liquid Argon ◽  
Dynamics Simulation ◽  
System Temperature ◽  
Solid Copper

AbstractA model nanofluid system of copper nanoparticles in argon base fluid was successfully modeled by molecular dynamics simulation. The interatomic interactions between solid copper nanoparticles, base liquid argon atoms and between solid copper and liquid argon were modeled by Lennard Jones potential with appropriate parameters. The effective thermal conductivity of the nanofluids was calculated through Green Kubo method in equilibrium molecular dynamics simulation for varying nanoparticle concentrations and for varying system temperatures. Thermal conductivity of the basefluid was also calculated for comparison. This study showed that effective thermal conductivity of nanofluids is much higher than that of the base fluid and found to increase with increased nanoparticle concentration and system temperature. Through molecular dynamics calculation of mean square displacements for basefluid, nanofluid and its components, we suggested that the increased movement of liquid atoms in the presence of nanoparticle was probable mechanism for higher thermal conductivity of nanofluids.

Thermal conductivity and interfacial Thermal Resistance Behavior for the Polyaniline (C3N)– boron carbide (BC3) Heterostructure

2021 ◽  
Author(s):  
Arian Mayelifartash ◽  
Mohammad Ali Abdol ◽  
Sadegh Sadeghzadeh
Keyword(s):  
Thermal Conductivity ◽  
Molecular Dynamics ◽  
Thermal Resistance ◽  
Boron Carbide ◽  
Molecular Dynamics Simulations ◽  
Thermal Conductance ◽  
Interfacial Thermal Resistance ◽  
Non Equilibrium Molecular Dynamics ◽  
Dynamics Simulations ◽  
Non Equilibrium

In this paper, by employing non-equilibrium molecular dynamics simulations (NEMD), the thermal conductance of hybrid formed by polyaniline (C3N) and boron carbide (BC3) in both armchair and zigzag configurations has...

Void and Dislocation Microstructure Development in Heteroepitaxial Film Growth

1995 ◽  
Vol 399 ◽  
Author(s):  
Richard W. Smith ◽  
David J. Srolovitz
Keyword(s):  
Thin Films ◽  
Molecular Dynamics ◽  
Film Growth ◽  
Lattice Misfit ◽  
Two Dimensional ◽  
Microstructure Development ◽  
Non Equilibrium Molecular Dynamics ◽  
Dynamics Simulations ◽  
Film Substrate ◽  
Edge Dislocations

ABSTRACTTwo dimensional, non-equilibrium molecular dynamics simulations have been performed to examine the microstructures of both homoepitaxial and heteroepitaxial thin films grown on single crystal substrates. The principal microstructural features to develop within these films are small voids and edge dislocations. Voids form near the surface of the growing film as surface depressions between microcolumns pinch off to become closed volumes. These voids often form in such a way as to introduce dislocations into the crystal with their cores positioned within the voids. Dislocations are also formed during heteroepitaxy at the interface between the substrate and film. These dislocations tend to be mobile. When voids are present in the film and when the lattice misfit is low, dislocations tend to be trapped in the voids or pulled toward them due to dislocation image interactions. Once attached to voids, dislocations are effectively pinned there. When voids are absent or when the misfit is high, dislocations are restricted to the film-substrate interface. In the case of heteroepitaxy, dislocations are found to relieve either tensile or compressive misfit stresses. Misfit stresses may also be accommodated, to some extent, merely by the free volume of the voids themselves.

Sign in / Sign up

Export Citation Format

Share Document