Numerical Analysis of the Effect of Carbon Monoxide Addition on&nbsp;Soot Formation in an Acetylene/Air Premixed Flame

Abstract Characteristics of non-premixed flames such as flame height and lift-off height are affected by the presence of magnetic fields due to the paramagnetic properties of some combustion species. However, it is unknown whether magnetic fields can be used to reduce the emission of pollutants in non-premixed flames. In general, pollutant emissions are reduced in combustion systems if the mixing of combustion species is enhanced during the process. Since paramagnetic combustion species such as O2, O, OH, HO2, etc have a preferential motion direction in the presence of magnetic fields, there is a potential to harness this effect of mixing by imposing a magnetic field on the flame. This study seeks to provide some insights on the effect of magnetic field on pollutants generated in a laminar non-premixed flame numerically. The non-premixed flame is simulated using a detailed chemical mechanism for propane-air combustion and a modified Moss-Brookes soot model. To simulate the effect of magnetism on the paramagnetic chemical species, the species paramagnetic susceptibility is computed using the Curie relation. The non-premixed flame is placed at three different locations within the magnetic field. The computation predicted that the amount of average pollutants reduction is dependent on the location of the flames within the magnetic fields with respect to magnetic gradients. The mass weighted average of the soot volume fraction over the computational domain decreased when the non-premixed flame is located at certain locations within the magnetic field of the solenoid with respect to the absence of the magnetic fields, but increases in other locations.

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Wet Partial Oxidation of JP8 in a Well-Insulated Reactor

ASME 2016 Power Conference ◽

10.1115/power2016-59515 ◽

2016 ◽

Author(s):

Richard Scenna ◽

Ashwani K. Gupta

Keyword(s):

Carbon Monoxide ◽

Power Systems ◽

Partial Oxidation ◽

Soot Formation ◽

Catalytic Reforming ◽

High Sulfur Content ◽

Reaction Regime ◽

Reduced Costs ◽

Direct Use ◽

Reforming Reactions

This work investigates wet and dry non-catalytic partial oxidation of JP8 under distributed reaction regime condition. Previous works have demonstrated the potential of the distributed reaction regime to increase hydrogen and carbon monoxide production over conventional non-catalytic reforming and suppress soot formation inside the reactor. Jet propellant 8 (JP8) has a high sulfur content (up to 3000ppm) and a tendency to form coke, making it an ideal candidate for this non-catalytic approach. Experimental results are reported with the reactor operated at fixed oxygen to carbon ratio of 1.08 and steam to carbon ratios varied from 0.0 to 0.23. Numerical simulations were used to determine flame regime and extent of distribution. Steam provided favorable effects even with trace amounts (S/C=0.01), but more pronounced effects were observed at steam to carbon ratio of 0.17. Syngas composed of 22.5–24.6% hydrogen and 20.1–23.3% carbon monoxide was evolved. Of the hydrocarbons detected, only methane was seen in finite amounts (0.17–0.29%). The increase in performance in terms of reforming efficiency and conversion exceeded what can be ascribed to steam reforming reactions alone. Additional enhancement is attributed to distributed reaction in the reactor. Reforming efficiency of approximately 68–80% is comparable to that from catalytic reforming. Low steam to carbon ratio offers higher sustainability in mobile power systems at reduced costs from direct use of water recovered from fuel cells.

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Numerical Analysis on Ignition of a Single Fuel Droplet Passing Through Premixed Flame.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.64.2148 ◽

1998 ◽

Vol 64 (623) ◽

pp. 2148-2154 ◽

Cited By ~ 1

Author(s):

Kan KOBAYASHI ◽

Yiguang JU ◽

Takashi NIIOKA

Keyword(s):

Numerical Analysis ◽

Premixed Flame ◽

Fuel Droplet

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Modelling of Soot Formation in a Laminar Coflow Non-premixed Flame with a Detailed CFD-Population Balance Model

Procedia Engineering ◽

10.1016/j.proeng.2015.01.258 ◽

2015 ◽

Vol 102 ◽

pp. 1274-1283 ◽

Cited By ~ 3

Author(s):

Petros Akridis ◽

Stelios Rigopoulos

Keyword(s):

Soot Formation ◽

Population Balance ◽

Premixed Flame ◽

Balance Model ◽

Population Balance Model

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Soot Formation Reaction Effect in Modeling Thermal Partial Oxidation of Jet-A

Volume 1: Fuels and Combustion, Material Handling, Emissions; Steam Generators; Heat Exchangers and Cooling Systems; Turbines, Generators and Auxiliaries; Plant Operations and Maintenance; Reliability, Availability and Maintainability (RAM); Plant Systems, Structures, Components and Materials Issues ◽

10.1115/power2014-32252 ◽

2014 ◽

Cited By ~ 1

Author(s):

Richard Scenna ◽

Ashwani K. Gupta

Keyword(s):

Experimental Data ◽

Carbon Monoxide ◽

Partial Oxidation ◽

Kinetic Models ◽

Soot Formation ◽

Radical Formation ◽

Fuel Reforming ◽

Chemical Modeling ◽

Formation Reaction ◽

One Dimensional

The results obtained from the modeling of thermal partial oxidation of kerosene based Jet-A fuel are presented using one dimensional chemical modeling. Two detailed kinetic models for alkenes chemistry ranging between C8 to C16 were evaluated and compared against experimental data of thermal partial oxidation of Jet-A fuel. The key difference between these two kinetic models was the inclusion of model for soot formation reactions. Chemical modeling was performed using dodecane to represent Jet-A fuel. The results showed that the model with soot reactions was significantly more accurate in predicting reformate products from Jet-A. In particular, the formation of carbon monoxide, methane and acetylene closely followed the experimental data with the model that included soot formation reactions. The results revealed that the soot formation reactions promoted the smaller hydrocarbons to decompose via the alternate kinetic pathways and from additional radical formation. The results also reveal that the inclusions of soot formation reactions are critical in the modeling of thermal partial oxidation of fuels for fuel reforming.

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