Absorption spectra of four types of diesel fuel are studied experimentally in the range between 0.2 μm and 6 μm. The ageing process of fuels is simulated by prolonged boiling. The average absorption efficiency factor of droplets is assumed to be proportional to $ardb,$ where $rd$ is the droplet radius, and a and b are polynomial functions of external gas temperature. Explicit expressions for a and b are derived for diesel fuel droplets in various realistic droplet radii and external gas temperature ranges for all four types of fuel.

1.
Lage
,
P. L. C.
, and
Rangel
,
R. H.
,
1993
, “
Single Droplet Vaporization Including Thermal Radiation Absorption
,”
J. Thermophys. Heat Transfer
,
7
(
3
), pp.
502
509
.
2.
Dombrovsky
,
L. A.
, and
Sazhin
,
S. S.
,
2003
, “
Absorption of Thermal Radiation in a Semi-Transparent Spherical Droplet: A Simplified Model
,”
Int. J. Heat Fluid Flow
,
24
(
6
), pp.
919
927
.
3.
Dombrovsky
,
L. A.
,
Sazhin
,
S. S.
,
Sazhina
,
E. M.
,
Feng
,
G.
,
Heikal
,
M. R.
,
Bardsley
,
M. E. A.
, and
Mikhalovsky
,
S. V.
,
2001
, “
Heating and Evaporation of Semi-Transparent Diesel Fuel Droplets in the Presence of Thermal Radiation
,”
Fuel
,
80
(
11
), pp.
1535
1544
.
4.
Marchese
,
A. J.
, and
Dryer
,
F. L.
,
1997
, “
The Effect of Non-Luminous Thermal Radiation in Microgravity Droplet Combustion
,”
Combust. Sci. Technol.
,
124
, pp.
371
402
.
5.
Sazhin
,
S. S.
,
Sazhina
,
E. M.
, and
Heikal
,
M. R.
,
2000
, “
Modelling of the Gas to Fuel Droplets Radiative Exchange
,”
Fuel
,
79
, pp.
1843
1852
.
6.
Dombrovsky
,
L. A.
,
Sazhin
,
S. S.
,
Mikhalovsky
,
S. V.
,
Wood
,
R.
, and
Heikal
,
M. R.
,
2003
, “
Spectral Properties of Diesel Fuel Droplets
,”
Fuel
,
82
(
1
), pp.
15
22
.
7.
Dombrovsky
,
L. A.
,
2002
, “
A Spectral Model of Absorption and Scattering of Thermal Radiation by Diesel Fuel Droplets
,”
High Temp.
,
40
(
2
), pp.
242
248
.
8.
Dombrovsky, L. A., Sazhin, S. S., and Heikal, M. R., 2002, “A Model for Computation of Radiative Characteristics of Diesel Fuel Droplets,” Proceedings of 3rd Russian National Heat and Mass Transfer Conference, 6, pp. 262–265 (in Russian).
9.
Ahrenkiel
,
R. K.
,
1971
, “
Modified Kramers-Kro¨nig Analysis of Optical Spectra
,”
J. Opt. Soc. Am.
,
61
, pp.
1651
1655
.
10.
Sazhina, E. M., Sazhin, S. S., Heikal, M. R., and Bardsley, M. E. A., 2000, “The P-1 Model for Thermal Radiation Transfer: Application to Numerical Modelling of Combustion Processes in Diesel Engines,” in Proceedings of the 16th IMACS World Congress 2000 on Scientific Computation, Applied Mathematics and Simulation, Paper 125-10, CD-ROM.