Mechanisms Controlling Soot Formation in Diffusion Flames PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Mechanisms Controlling Soot Formation in Diffusion Flames PDF full book. Access full book title Mechanisms Controlling Soot Formation in Diffusion Flames by . Download full books in PDF and EPUB format.
Author: Publisher: ISBN: Category : Languages : en Pages : 94
Book Description
Arclength continuation methods were incorporated into a code for predicting the structure of sooting, opposed-jet flames. The code includes complex chemistry, detailed particle dynamics, particle chemistry and radiation. The code was used to predict soot production over a wide variation in strain rates for both ethylene/air and methane/air diffusion flames. Predicted values (both peak and spatial distributions) agree well with experimental measurements in ethylene flames. Particle size distributions are also predicted using the aerosol equations from MAEROS, but no data is available for comparison. Also, the soot dynamical equations were imbedded into a separate code to describe soot production in a coflow, laminar, diffusion flame which includes treatment of detailed, gas phase chemistry. Predictions were compared to measurements made in a methane, coflow flame. Reasonable agreement between the predictions and measurements was obtained, although a factor of three underprediction of the soot volume fractions is likely due to uncertainties in inlet conditions and an inability to match closely bulk flame parameters such as temperature. Predicted peak soot production occurred around 1720K and particle oxidation was dominated by superequilibrium concentrations of hydroxyl radicals. Several PAH-forming sequences were examined and compared to the traditional acetylene-addition sequence. A sequence involving benzyl-propargyl combination was found to compete with the traditional mechanism and it should be included in future analyses. The algorithms for treating sectional soot dynamics and growth/oxidation rates were modified to include effects at high pressure. Continuum effects and limitations to gaseous diffusion were included in the opposed jet code. Predicted variations in soot production due to pressure changes from 4 to 10 atmospheres were made for an ethylene-air.
Author: Publisher: ISBN: Category : Languages : en Pages : 94
Book Description
Arclength continuation methods were incorporated into a code for predicting the structure of sooting, opposed-jet flames. The code includes complex chemistry, detailed particle dynamics, particle chemistry and radiation. The code was used to predict soot production over a wide variation in strain rates for both ethylene/air and methane/air diffusion flames. Predicted values (both peak and spatial distributions) agree well with experimental measurements in ethylene flames. Particle size distributions are also predicted using the aerosol equations from MAEROS, but no data is available for comparison. Also, the soot dynamical equations were imbedded into a separate code to describe soot production in a coflow, laminar, diffusion flame which includes treatment of detailed, gas phase chemistry. Predictions were compared to measurements made in a methane, coflow flame. Reasonable agreement between the predictions and measurements was obtained, although a factor of three underprediction of the soot volume fractions is likely due to uncertainties in inlet conditions and an inability to match closely bulk flame parameters such as temperature. Predicted peak soot production occurred around 1720K and particle oxidation was dominated by superequilibrium concentrations of hydroxyl radicals. Several PAH-forming sequences were examined and compared to the traditional acetylene-addition sequence. A sequence involving benzyl-propargyl combination was found to compete with the traditional mechanism and it should be included in future analyses. The algorithms for treating sectional soot dynamics and growth/oxidation rates were modified to include effects at high pressure. Continuum effects and limitations to gaseous diffusion were included in the opposed jet code. Predicted variations in soot production due to pressure changes from 4 to 10 atmospheres were made for an ethylene-air.
Author: Henning Bockhorn Publisher: Springer Science & Business Media ISBN: 3642851673 Category : Science Languages : en Pages : 595
Book Description
Soot Formation in Combustion represents an up-to-date overview. The contributions trace back to the 1991 Heidelberg symposium entitled "Mechanism and Models of Soot Formation" and have all been reedited by Prof. Bockhorn in close contact with the original authors. The book gives an easy introduction to the field for newcomers, and provides detailed treatments for the specialists. The following list of contents illustrates the topics under review:
Author: J. Lahaye Publisher: Springer Science & Business Media ISBN: 1468444638 Category : Science Languages : en Pages : 429
Book Description
Our interest in Mulhouse for carbon black and soot began some 30 years ago when J.B. Donnet developed the concept of surface chemistry of carbon and its involvement in interactions with gas, liquid and solid phases. In the late sixties, we began to study soot formation in pyrolytic systems and later on in flames. The idea of organ1z1ng a meeting on soot formation originated some four or five years ago, through discussions among Professor J.B. Howard, Dr. A. D'Alessio and ourselves. At that time the scientific community was becoming aware of the necessity to strictly control soot formation and emission. Being involved in the study of surface properties of carbon black as well as of formation of soot, we realized that the combustion community was not always fully aware of the progress made by the physical-chemists on carbon black. Reciprocally, the carbon specialists were often ignoring the research carried out on soot in flames. One objective of this workshop was to stimulate discussions between these two scientific communities. During the preparation of the meeting, and especially during the review process by the Material Science Committee of the Scientific Affairs Division of N.A.T.O. the toxicological aspect emerged as being an important component to be addressed during the workshop. To reflect these preoccupations we invited biologists, physical chemists and engineers, all leaders in their field. The final programme is a compromise of the different aspects of the subject and was divided in five sessions.
Author: Hojoon Chang Publisher: ISBN: Category : Combustion Languages : en Pages :
Book Description
The present work focuses on a computational study of a simplified soot model to predict soot production and destruction in methane/oxidizer (O2 and N2) and ethylene/air flames using a one-dimensional laminar opposed diffusion flame setup. Two different detailed reaction mechanisms (361 reactions & 61 species for methane/oxidizer flame and 527 reactions & 99 species for ethylene/air flame) are used to validate the simplified soot model in each flame. The effects of strain rate and oxygen content on the soot production and destruction are studied, and the soot related properties such as soot volume fraction, particle number density and particle diameter are compared with published results. The results show reasonable agreement with data and that the soot volume fraction decreases with higher strain rate and lower oxygen content. The simplified soot model has also been used with two reduced reaction mechanisms (12-step, 16-species for methane flame and 20-species for ethylene flame) since such reduced mechanisms are computationally more efficient for practical application. The profiles of the physical properties and the major species are in excellent agreement with the results using the detailed reaction mechanisms. However, minor hydrocarbon-species such as acetylene (C2H2) that is the primary pyrolysis species in the simplified soot model is significantly over predicted and this, in turn, results in an over-prediction of soot production. Finally, the reduced reaction mechanism is modified to get more accurate prediction of the minor hydrocarbon-species. The modified reduced reaction mechanism shows that the soot prediction can be improved by improving the predictions of the key minor species.
Author: Donald Siegla Publisher: Springer Science & Business Media ISBN: 1475761376 Category : Technology & Engineering Languages : en Pages : 500
Book Description
The goal of the symposium, "Particulate Carbon: Formation During Combustion", held at the General Motors Research Laboratories on October 15 and 16, 1980, was to discuss fundamental aspects of soot formation and oxidation in combustion systems and to stimulate new research by extensive interactions among the participants. This book contains lhe papers and discussions of that symposium, the 26th in an annual series covering many different disciplines which are timely and of interest to both General Motors and the technical community at large. The subject of this symposium has considerable relevance for man in his effort to control and preserve his environment. Emission of particulate carbon into the atmos phere from combustion sources is of concern to scientists and laymen alike. The hope of reducing this emission clearly requires an understanding of its formation during the combustion process, itself an area of considerable long-term research interest. It is our hope that this symposium has served to summarize what is known so that what remains to be learned can be pursued with greater vigor.
Author: 
Author: 
Author: Henning Bockhorn
Author: R. J. Santoro
Author: J. Lahaye
Author: Chul Han Kim
Author: Henning Bockhorn
Author: Hojoon Chang
Author: Guozheng Lin
Author: Richard L. Axelbaum
Author: Donald Siegla