Conceptual Examination of Gas Phase Particulate Formation in Gas Turbine Combustors

Recent laboratory studies of droplet combustion indicate the potential for substantial gas phase particulate formation even with single component hydrocarbon fuels. Formation of large particles has been observed in the neighborhood of burning droplet arrays, particularly when the droplets are closely spaced. To provide insight into the potential for particulate formation during the combustion of fuel droplet sprays in gas turbine combustors, a mathematical framework is developed for examining the formation of soot nuclei in droplet combustion. A simplified model of the chemistry of fuel pyrolysis and nuclei formation is used and a series of calculations is made to explore the sensitivity of soot nuclei formation to conditions typical of gas turbine combustion systems.

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Infrared spectra of complex organic molecules in astronomically relevant ice matrices

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731998 ◽

2018 ◽

Vol 611 ◽

pp. A35 ◽

Cited By ~ 9

Author(s):

J. Terwisscha van Scheltinga ◽

N. F. W. Ligterink ◽

A. C. A. Boogert ◽

E. F. van Dishoeck ◽

H. Linnartz

Keyword(s):

Gas Phase ◽

Dimethyl Ether ◽

Organic Molecules ◽

Laboratory Data ◽

Laboratory Studies ◽

Astronomical Data ◽

Astronomical Observations ◽

Circumstellar Gas ◽

Complex Organic ◽

Recent Laboratory

Context. The number of identified complex organic molecules (COMs) in inter- and circumstellar gas-phase environments is steadily increasing. Recent laboratory studies show that many such species form on icy dust grains. At present only smaller molecular species have been directly identified in space in the solid state. Accurate spectroscopic laboratory data of frozen COMs, embedded in ice matrices containing ingredients related to their formation scheme, are still largely lacking.Aim. This work provides infrared reference spectra of acetaldehyde (CH3CHO), ethanol (CH3CH2OH), and dimethyl ether (CH3OCH3) recorded in a variety of ice environments and for astronomically relevant temperatures, as needed to guide or interpret astronomical observations, specifically for upcoming James Webb Space Telescope observations.Methods. Fourier transform transmission spectroscopy (500–4000 cm−1/20–2.5 μm, 1.0 cm−1 resolution) was used to investigate solid acetaldehyde, ethanol and dimethyl ether, pure or mixed with water, CO, methanol, or CO:methanol. These species were deposited on a cryogenically cooled infrared transmissive window at 15 K. A heating ramp was applied, during which IR spectra were recorded until all ice constituents were thermally desorbed.Results. We present a large number of reference spectra that can be compared with astronomical data. Accurate band positions and band widths are provided for the studied ice mixtures and temperatures. Special efforts have been put into those bands of each molecule that are best suited for identification. For acetaldehyde the 7.427 and 5.803 μm bands are recommended, for ethanol the 11.36 and 7.240 μm bands are good candidates, and for dimethyl ether bands at 9.141 and 8.011 μm can be used. All spectra are publicly available in the Leiden Database for Ice.

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Infrared spectra of complex organic molecules in astronomically relevant ice matrices

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319008780 ◽

2019 ◽

Vol 15 (S350) ◽

pp. 356-357

Author(s):

J. Terwisscha van Scheltinga ◽

N. F. W. Ligterink ◽

A. C. A. Boogert ◽

E. F. van Dishoeck ◽

H. Linnartz

Keyword(s):

Solid State ◽

Gas Phase ◽

Infrared Spectra ◽

Organic Molecules ◽

Laboratory Studies ◽

Astronomical Observations ◽

James Webb Space Telescope ◽

Circumstellar Gas ◽

Complex Organic ◽

Recent Laboratory

AbstractThe identification of complex organic molecules, COMs, in inter- and circumstellar gas phase environments is steadily increasing. The formation of such COMs takes largely place on the icy dust grains, as has been shown in recent laboratory studies. Until now solid state features of smaller molecular species have been directly identified in these environments. The presented work on acetaldehyde (CH3CHO), ethanol (CH3CH2OH), and dimethyl ether (CH3OCH3) in different astronomically relevant ice environments and for temperatures in the range 15 to 160 Kelvin, provides the necessary tools to guide or interpret astronomical observations, specifically for upcoming James Webb Space Telescope observations.

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Carbon Formation by the Pyrolysis of Gas Turbine Fuels in Preflame Regions of Gas Turbine Combustors

Volume 3: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/82-gt-84 ◽

1982 ◽

Cited By ~ 2

Author(s):

C. D. Hurley

Keyword(s):

Gas Turbine ◽

Gas Phase ◽

Carbon Formation ◽

Temperature Range ◽

Gas Turbine Combustors ◽

Liquid Phases ◽

Series Of Experiments ◽

Kinetics Of

A series of experiments have been carried out to investigate the formation of carbon from the pyrolysis of gas turbine fuels, in both the gas and liquid phases, over the temperature range 573–1300 K. Two fuels were examined, a kerosine and a diesel, spanning the range of current and possible future aviation fuels. It was found that only gas phase pyrolysis could account for the formation of carbon and that there was no difference in the carbon forming tendencies of kerosine and diesel. The kinetics of the reaction were determined, making it possible to predict the amount of decomposition of the fuels at temperatures up to those typical of preflame regions of combustors.

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