Gas-phase entropy generation during transient methanol droplet combustion

Daniel N. Pope, Vasudevan Raghavan, George Gogos

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

A numerical model was used to investigate gas-phase entropy generation during transient methanol droplet combustion in a low-pressure, zero-gravity, air environment.A comprehensive formulation for the entropy generation in a multi-component reacting flow is derived. Stationary methanol droplet combustion in a low ambient temperature (300 K) and a nearly quiescent atmosphere was studied and the effect of surface tension on entropy generation is discussed. Results show that the average entropy generation rate over the droplet lifetime is higher for the case that neglects surface tension. Entropy generation during the combustion of methanol droplets moving in a high-temperature environment (1200 K), as seen in a typical spray combustion system, is also presented. Entropy generation due to chemical reaction increases and entropy generation due to heat and mass transfer decreases with an increase in initial Reynolds number over the range of initial Reynolds numbers (1-100) considered. Contributions due to heat transfer and chemical reaction to the total entropy generation are greater than the contribution due to mass transfer. Entropy generation due to coupling between heat and mass transfer is negligible. For moving droplets, the lifetime averaged entropy generation rate presents a minimum value at an initial Reynolds number of approximately 55.

Original languageEnglish (US)
Pages (from-to)1288-1302
Number of pages15
JournalInternational Journal of Thermal Sciences
Volume49
Issue number7
DOIs
StatePublished - Jul 1 2010

Fingerprint

Methanol
Entropy
methyl alcohol
entropy
vapor phases
Gases
mass transfer
Reynolds number
Mass transfer
heat transfer
Heat transfer
Surface tension
Chemical reactions
chemical reactions
interfacial tension
high temperature environments
weightlessness
reacting flow
life (durability)
ambient temperature

Keywords

  • Droplet combustion
  • Entropy generation
  • Methanol
  • Numerical model
  • Surface tension

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Engineering(all)

Cite this

Gas-phase entropy generation during transient methanol droplet combustion. / Pope, Daniel N.; Raghavan, Vasudevan; Gogos, George.

In: International Journal of Thermal Sciences, Vol. 49, No. 7, 01.07.2010, p. 1288-1302.

Research output: Contribution to journalArticle

@article{68203c3c137b45c3bc662ce5d4c320e2,
title = "Gas-phase entropy generation during transient methanol droplet combustion",
abstract = "A numerical model was used to investigate gas-phase entropy generation during transient methanol droplet combustion in a low-pressure, zero-gravity, air environment.A comprehensive formulation for the entropy generation in a multi-component reacting flow is derived. Stationary methanol droplet combustion in a low ambient temperature (300 K) and a nearly quiescent atmosphere was studied and the effect of surface tension on entropy generation is discussed. Results show that the average entropy generation rate over the droplet lifetime is higher for the case that neglects surface tension. Entropy generation during the combustion of methanol droplets moving in a high-temperature environment (1200 K), as seen in a typical spray combustion system, is also presented. Entropy generation due to chemical reaction increases and entropy generation due to heat and mass transfer decreases with an increase in initial Reynolds number over the range of initial Reynolds numbers (1-100) considered. Contributions due to heat transfer and chemical reaction to the total entropy generation are greater than the contribution due to mass transfer. Entropy generation due to coupling between heat and mass transfer is negligible. For moving droplets, the lifetime averaged entropy generation rate presents a minimum value at an initial Reynolds number of approximately 55.",
keywords = "Droplet combustion, Entropy generation, Methanol, Numerical model, Surface tension",
author = "Pope, {Daniel N.} and Vasudevan Raghavan and George Gogos",
year = "2010",
month = "7",
day = "1",
doi = "10.1016/j.ijthermalsci.2010.02.012",
language = "English (US)",
volume = "49",
pages = "1288--1302",
journal = "International Journal of Thermal Sciences",
issn = "1290-0729",
publisher = "Elsevier Masson SAS",
number = "7",

}

TY - JOUR

T1 - Gas-phase entropy generation during transient methanol droplet combustion

AU - Pope, Daniel N.

AU - Raghavan, Vasudevan

AU - Gogos, George

PY - 2010/7/1

Y1 - 2010/7/1

N2 - A numerical model was used to investigate gas-phase entropy generation during transient methanol droplet combustion in a low-pressure, zero-gravity, air environment.A comprehensive formulation for the entropy generation in a multi-component reacting flow is derived. Stationary methanol droplet combustion in a low ambient temperature (300 K) and a nearly quiescent atmosphere was studied and the effect of surface tension on entropy generation is discussed. Results show that the average entropy generation rate over the droplet lifetime is higher for the case that neglects surface tension. Entropy generation during the combustion of methanol droplets moving in a high-temperature environment (1200 K), as seen in a typical spray combustion system, is also presented. Entropy generation due to chemical reaction increases and entropy generation due to heat and mass transfer decreases with an increase in initial Reynolds number over the range of initial Reynolds numbers (1-100) considered. Contributions due to heat transfer and chemical reaction to the total entropy generation are greater than the contribution due to mass transfer. Entropy generation due to coupling between heat and mass transfer is negligible. For moving droplets, the lifetime averaged entropy generation rate presents a minimum value at an initial Reynolds number of approximately 55.

AB - A numerical model was used to investigate gas-phase entropy generation during transient methanol droplet combustion in a low-pressure, zero-gravity, air environment.A comprehensive formulation for the entropy generation in a multi-component reacting flow is derived. Stationary methanol droplet combustion in a low ambient temperature (300 K) and a nearly quiescent atmosphere was studied and the effect of surface tension on entropy generation is discussed. Results show that the average entropy generation rate over the droplet lifetime is higher for the case that neglects surface tension. Entropy generation during the combustion of methanol droplets moving in a high-temperature environment (1200 K), as seen in a typical spray combustion system, is also presented. Entropy generation due to chemical reaction increases and entropy generation due to heat and mass transfer decreases with an increase in initial Reynolds number over the range of initial Reynolds numbers (1-100) considered. Contributions due to heat transfer and chemical reaction to the total entropy generation are greater than the contribution due to mass transfer. Entropy generation due to coupling between heat and mass transfer is negligible. For moving droplets, the lifetime averaged entropy generation rate presents a minimum value at an initial Reynolds number of approximately 55.

KW - Droplet combustion

KW - Entropy generation

KW - Methanol

KW - Numerical model

KW - Surface tension

UR - http://www.scopus.com/inward/record.url?scp=77955230540&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77955230540&partnerID=8YFLogxK

U2 - 10.1016/j.ijthermalsci.2010.02.012

DO - 10.1016/j.ijthermalsci.2010.02.012

M3 - Article

AN - SCOPUS:77955230540

VL - 49

SP - 1288

EP - 1302

JO - International Journal of Thermal Sciences

JF - International Journal of Thermal Sciences

SN - 1290-0729

IS - 7

ER -