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Title: Molecular dynamics study on the effect of boundary heating rate on the phase change characteristics of thin film liquid

Abstract

In this study, theoretical investigation of thin film liquid phase change phenomena under different boundary heating rates has been conducted with the help of molecular dynamics simulation. To do this, the case of argon boiling over a platinum surface has been considered. The study has been conducted to get a better understanding of the nano-scale physics of evaporation/boiling for a three phase system with particular emphasis on the effect of boundary heating rate. The simulation domain consisted of liquid and vapor argon atoms placed over a platinum wall. Initially the whole system was brought to an equilibrium state at 90 K with the help of equilibrium molecular dynamics and then the temperature of the bottom wall was increased to a higher temperature (250 K/130 K) over a finite heating period. Depending on the heating period, the boundary heating rate has been varied in the range of 1600×10{sup 9} K/s to 8×10{sup 9} K/s. The variations of argon region temperature, pressure, net evaporation number with respect to time under different boundary heating rates have been determined and discussed. The heat fluxes normal to platinum wall for different cases were also calculated and compared with theoretical upper limit of maximum possible heatmore » transfer to elucidate the effect of boundary heating rate.« less

Authors:
; ; ;  [1]
  1. Department of Mechanical Engineering, Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 (Bangladesh)
Publication Date:
OSTI Identifier:
22608551
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1754; Journal Issue: 1; Conference: ICME 2015: 11. international conference on mechanical engineering, Dhaka (Bangladesh), 18-20 Dec 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ARGON; EQUILIBRIUM; EVAPORATION; HEAT; HEAT FLUX; HEAT TRANSFER; HEATING RATE; LIQUIDS; MOLECULAR DYNAMICS METHOD; PLATINUM; SIMULATION; SURFACES; THIN FILMS

Citation Formats

Hasan, Mohammad Nasim, E-mail: nasim@me.buet.ac.bd.com, Morshed, A. K. M. Monjur, E-mail: shavik@me.buet.ac.bd.com, Rabbi, Kazi Fazle, E-mail: rabbi35.me10@gmail.com, and Haque, Mominul, E-mail: mominulmarup@gmail.com. Molecular dynamics study on the effect of boundary heating rate on the phase change characteristics of thin film liquid. United States: N. p., 2016. Web. doi:10.1063/1.4958379.
Hasan, Mohammad Nasim, E-mail: nasim@me.buet.ac.bd.com, Morshed, A. K. M. Monjur, E-mail: shavik@me.buet.ac.bd.com, Rabbi, Kazi Fazle, E-mail: rabbi35.me10@gmail.com, & Haque, Mominul, E-mail: mominulmarup@gmail.com. Molecular dynamics study on the effect of boundary heating rate on the phase change characteristics of thin film liquid. United States. doi:10.1063/1.4958379.
Hasan, Mohammad Nasim, E-mail: nasim@me.buet.ac.bd.com, Morshed, A. K. M. Monjur, E-mail: shavik@me.buet.ac.bd.com, Rabbi, Kazi Fazle, E-mail: rabbi35.me10@gmail.com, and Haque, Mominul, E-mail: mominulmarup@gmail.com. 2016. "Molecular dynamics study on the effect of boundary heating rate on the phase change characteristics of thin film liquid". United States. doi:10.1063/1.4958379.
@article{osti_22608551,
title = {Molecular dynamics study on the effect of boundary heating rate on the phase change characteristics of thin film liquid},
author = {Hasan, Mohammad Nasim, E-mail: nasim@me.buet.ac.bd.com and Morshed, A. K. M. Monjur, E-mail: shavik@me.buet.ac.bd.com and Rabbi, Kazi Fazle, E-mail: rabbi35.me10@gmail.com and Haque, Mominul, E-mail: mominulmarup@gmail.com},
abstractNote = {In this study, theoretical investigation of thin film liquid phase change phenomena under different boundary heating rates has been conducted with the help of molecular dynamics simulation. To do this, the case of argon boiling over a platinum surface has been considered. The study has been conducted to get a better understanding of the nano-scale physics of evaporation/boiling for a three phase system with particular emphasis on the effect of boundary heating rate. The simulation domain consisted of liquid and vapor argon atoms placed over a platinum wall. Initially the whole system was brought to an equilibrium state at 90 K with the help of equilibrium molecular dynamics and then the temperature of the bottom wall was increased to a higher temperature (250 K/130 K) over a finite heating period. Depending on the heating period, the boundary heating rate has been varied in the range of 1600×10{sup 9} K/s to 8×10{sup 9} K/s. The variations of argon region temperature, pressure, net evaporation number with respect to time under different boundary heating rates have been determined and discussed. The heat fluxes normal to platinum wall for different cases were also calculated and compared with theoretical upper limit of maximum possible heat transfer to elucidate the effect of boundary heating rate.},
doi = {10.1063/1.4958379},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1754,
place = {United States},
year = 2016,
month = 7
}
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