A numerical study of steady burning of spherical ethanol particles in a spray environment is presented. A spray environment is modeled as a high temperature oxidizer stream where the major products of combustion such as carbon dioxide and water vapor will be present along with reduced amounts of oxygen and nitrogen. The numerical model, which employs variable thermophysical properties, a global single-step reaction mechanism, and an optically thin radiation model, has been first validated against published experimental results for quasi-steady combustion of spherical ethanol particles. The validated model has been employed to predict the burning behavior of the ethanol particle in high temperature modified oxidizer environment. Results show that based on the amount of oxygen present in the oxidizer the burning rate constant is affected. The ambient temperature affects the burning rate constant only after a sufficient decrease in the oxygen content occurs. In pure air stream, ambient temperature variation does not affect the evaporation constant. Results in terms of burning rates, maximum temperature around the particle, and the evaporation rate constants are presented for all the cases. The variation of normalized Damköhler number is also presented to show the cases where combustion or pure evaporation would occur.

References

References
1.
Gajdeczko
,
B. F.
,
Luff
,
J.
,
Dryer
,
F. L.
, and
Lavid
,
M.
, 2000, “
Laser Ignition of Liquid Oxygen/Ethanol Propellants
,”
Twenty-Eighth Symposium (International) on Combustion: Abstracts of Work in Progress Poster Presentations (No. 2-B20)
,
The Combustion Institute
,
Pittsburgh, PA
, pp.
244
.
2.
Kumagai
,
S.
,
Sakai
,
T.
, and
Okajima
,
S.
, 1971, “
Combustion of Free Fuel Droplets in a Freely Falling Chamber
,”
Proc. Combust. Inst.
,
13
(
1
), pp.
779
785
.
3.
Gollahalli
,
S. R.
, and
Brzustowski
,
T. A.
, 1973, “
Experimental Studies on Flame Structure in the Wake Flame of a Burning Droplet
,”
Proc. Combust. Inst.
,
14
(
1
), pp.
1333
1344
.
4.
Okajima
,
S.
, and
Kumagai
,
S.
, 1982, “
Experimental Studies on Combustion of Fuel Droplets in a Flowing Air Under Zero and High-Gravity Conditions
,”
Proc. Combust. Inst.
,
19
(
1
), pp.
1021
1027
.
5.
Hara
,
H.
, and
Kumagai
,
S.
, 1994, “
The Effect of Initial Diameter on Free Droplet Combustion With Spherical Flames
,”
Proc. Combust. Inst.
,
25
(
1
), pp.
423
430
.
6.
Yozgatligil
,
A.
,
Park
,
S. H.
,
Choi
,
M. Y.
,
Kazakov
,
A.
, and
Dryer
,
F. L.
, 2007, “
Influence of Oxygen Concentration on the Sooting Behavior of Ethanol Droplet Flames in Microgravity Conditions
,”
Proc. Combust. Inst.
,
31
(
2
), pp.
2165
2173
.
7.
Parag
S.
, and
Raghavan
,
V.
, 2009, “
Experimental Investigation of Burning Rates of Pure Ethanol and Ethanol Blended Fuels
,”
Combust. Flame
,
156
(
5
), pp.
997
1005
.
8.
Hallett
,
W. L. H.
, and
Beauchamp-Kiss
,
S.
, 2010, “
Evaporation of Single Droplets of Ethanol–Fuel Oil Mixtures
,”
Fuel
,
89
(
9
), pp.
2496
2504
.
9.
Balakrishnan
,
P.
,
Sundararajan
,
T.
, and
Natarajan
,
R.
, 2001, “
Combustion of a Fuel Droplet in a Mixed Convective Environment
,”
Combust. Sci. Technol.
,
163
(
1
), pp.
77
106
.
10.
Mukhopadhyay
,
A.
, and
Sanyal
,
D.
, 2005, “
A Semi-Analytical Model for Evaporating Fuel Droplets
,”
ASME J. Heat Transfer
,
127
(
2
), pp.
199
203
.
11.
Pope
,
D. N.
, and
Gogos
,
G.
, 2005, “
Numerical Simulation of Fuel Droplet Extinction Due to Forced Convection
,”
J. Combust. Flame
,
142
, pp.
89
106
.
12.
Raghavan
,
V.
,
Babu
,
V.
,
Sundararajan
,
T.
, and
Natarajan
,
R.
, 2005, “
Flame Shapes and Burning Rates of Spherical Fuel Particles in a Mixed Convective Environment
,”
Int. J. Heat Mass Transfer
,
48
, pp.
5354
5370
.
13.
Egolfopoulos
,
F. N.
,
Du
,
D. X.
, and
Law
,
C. K.
, 1992, “
A Study on Ethanol Oxidation Kinetics in Laminar Premixed Flames, Flow Reactors, and Shock Tubes
,”
Proc. Combust. Inst.
,
24
, pp.
833
841
.
14.
Li
,
J.
,
Kazakov
,
A.
, and
Dryer
,
F. L.
, 2001, “
Ethanol Pyrolysis Experiments in a Variable Pressure Flow Reactor
,”
Int. J. Chem. Kinet.
,
133
, pp.
859
867
.
15.
Marinov
,
N. M.
, 1999, “
A Detailed Chemical Kinetic Model for High Temperature Ethanol Oxidation
,”
Int. J. Chem. Kinet.
,
31
, pp.
183
220
.
16.
Norton
,
T. S.
, and
Dryer
,
F. L.
, 1992, “
An Experimental and Modeling Study of Ethanol Oxidation Kinetics in an Atmospheric Pressure Flow Reactor
,”
Int. J. Chem. Kinet.
,
24
, pp.
319
344
.
17.
Kazakov
,
A.
,
Conley
,
J.
, and
Dryer
,
F. L.
, 2003, “
Detailed Modeling of Isolated Ethanol Droplet Combustion Under Microgravity Conditions
,”
Combust. Flame
,
134
(
4
), pp.
301
314
.
18.
Dubey
,
R.
,
Bhadraiah
,
K.
, and
Raghavan
,
V.
, 2011, “
On the Estimation and Validation of Global Single-Step Kinetics Parameters of Ethanol–Air Oxidation Using Diffusion Flame Extinction Data
,”
Combust. Sci. Technol.
,
183
(
1
), pp.
43
50
.
19.
Harpole
,
G. M.
, 1981, “
Droplet Evaporation in High Temperature Environments
,”
ASME J. Heat Transfer
,
103
(
1
), pp.
86
91
.
20.
Renksizbulut
,
M.
, and
Yuen
,
M. C.
, 1983, “
Experimental Study of Droplet Evaporation in a High-Temperature Air Stream
,”
ASME J. Heat Transfer
,
105
(
2
), pp.
384
388
.
21.
Renksizbulut
,
M.
, and
Yuen
,
M. C.
, 1983, “
Numerical Study of Droplet Evaporation in a High-Temperature Stream
,”
ASME J. Heat Transfer
,
105
(
2
), pp.
389
397
.
22.
Szekely
,
G. A.
, Jr.
, and
Faeth
,
G. M.
, 1983, “
Effects of Envelope Flames on Drop Gasification Rates in Turbulent Diffusion Flames
,”
Combust. Flame
,
49
, pp.
255
259
.
23.
Shinji
,
N.
,
Daisuke
,
S.
,
Toshikazu
,
K.
,
Yoshiaki
,
N.
, and
Tomoya
,
F.
, 2011, “
Combustion Behaviors of Isolated n-Decane and Ethanol Droplets in Carbon Dioxide-Rich Ambience Under Microgravity
,”
Proc. Combust. Inst.
,
33
(
2
), pp.
2031
2038
.
24.
Jin
,
Y.
, and
Shaw
,
B. D.
, 2010, “
Computational Modeling of n-Heptane Droplet Combustion in Air–Diluent Environments Under Reduced-Gravity
,”
Int. J. Heat Mass Transfer
,
53
(
25–26
), pp.
5782
5791
.
25.
Barlow
,
R. S.
,
Karpetis
,
A. N.
,
Frank
,
J. H.
, and
Chen
,
J. Y.
, 2001, “
Scalar Profiles and No Formation in Laminar Opposed-Flow Partially Pre-Mixed Methane/Air Flames
,”
Combust. Flames
,
127
(
3
), pp.
2102
2118
.
26.
Pope
,
D. N.
, and
Gogos
,
G.
, 2005, “
A New Multi-Component Diffusion Formulation for the Finite Volume Method: Application to Convective Droplet Combustion
,”
Numer. Heat Transfer Part B
,
48
(
3
), p.
213
.
You do not currently have access to this content.