Download or read book Effects of Fuel Doping and Fuel Chemistry on Soot Formation in Co flow Laminar Diffusion Flames at Elevated Pressures written by Silin Yang and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Effects of fuel doping and fuel chemistry on soot formation were studied in laminar diffusion flames at elevated pressures. Soot spectral emission is used to obtain radial temperature, soot volume fraction, and soot yield profiles. This thesis first investigated addition of 0%-40% ethanol in ethylene flames at 3-10 bar. 10% ethanol-doped flames didn't exhibit measurable soot synergy, whereas 20%-40% ethanol displayed lower soot yields. Secondly, 7.5% of benzene, cyclo-hexane and n-hexane was added into methane flames at 1.4-10 bar. Pressure dependence of sooting propensity is lowest for benzene. Thirdly, 3% of m-xylene and n-octane was mixed with methane at 1.4-10 bar. m-Xylene doped methane flames produced highest soot yields but lowest pressure dependency in soot yields. Results indicate that pressure dependence of highly sooting aromatics weakens compared to that of less sooting n-alkanes at high pressures.
Download or read book Soot Formation at High Pressures in Laminar Liquid and Gaseous Fuel Flames written by Adriana Elizabeth Daca and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soot Formation in Co flow and Counterflow Laminar Diffusion Flames of Fuel Mixtures written by Ahmet Emre Karatas and published by . This book was released on 2009 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the formation process of soot in the flames of even-carbon-numbered fuels, acetylene and its derivatives are suspected to be dominant. The addition of an odd-carbon-numbered fuel into these flames introduces methyl radicals and/or C3 chemistries, which are believed to (de)activate certain chemical pathways towards the production of soot. The resultant soot formation rate of the mixture could be higher than the sum of the respective rates of the mixture components, i.e., synergistic effect.In this work, the mixtures of butane isomers, ethylene-butane isomers, and propane-butane isomers were studied on a co-flow and a counterflow burner. Chemical effects were isolated from those of thermal and dilution by mixing isomers and comparing the mixtures including one isomer to those including the counterpart. Line of sight attenuation (LOSA) and laser-light extinction techniques were used for measuring soot volume fraction. The results provide information on synergistic effects in soot formation for the fuels used.
Download or read book Experimental and Numerical Studies for Soot Formation in Laminar Coflow Diffusion Flames of Jet A 1 and Synthetic Jet Fuels written by Meghdad Saffaripour and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soot Formation in Non premixed Laminar Flames at Subcritical and Supercritical Pressures written by Hyun Il Joo and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental study was conducted using axisymmetric co-flow laminar diffusion flames of methane-air, methane-oxygen and ethylene-air to examine the effect of pressure on soot formation and the structure of the temperature field. A liquid fuel burner was designed and built to observe the sooting behavior of methanol-air and n-heptane-air laminar diffusion flames at elevated pressures up to 50 atm. A non-intrusive, line-of-sight spectral soot emission (SSE) diagnostic technique was used to determine the temperature and the soot volume fraction of methane-air flames up to 60 atm, methane-oxygen flames up to 90 atm and ethylene-air flames up to 35 atm. The physical flame structure of the methane-air and methane-oxygen diffusion flames were characterized over the pressure range of 10 to 100 atm and up to 35 atm for ethylene-air flames. The flame height, marked by the visible soot radiation emission, remained relatively constant for methane-air and ethylene-air flames over their respected pressure ranges, while the visible flame height for the methane-oxygen flames was reduced by over 50 % between 10 and 100 atm. During methane-air experiments, observations of anomalous occurrence of liquid material formation at 60 atm and above were recorded. The maximum conversion of the carbon in the fuel to soot exhibited a strong power-law dependence on pressure. At pressures 10 to 30 atm, the pressure exponent is approximately 0.73 for methane-air flames. At higher pressures, between 30 and 60 atm, the pressure exponent is approximately 0.33. The maximum fuel carbon conversion to soot is 12.6 % at 60 atm. For methane-oxygen flames, the pressure exponent is approximately 1.2 for pressures between 10 and 40 atm. At pressures between 50 and 70 atm, the pressure exponent is about -3.8 and approximately -12 for 70 to 90 atm. The maximum fuel carbon conversion to soot is 2 % at 40 atm. For ethylene-air flames, the pressure exponent is approximately 1.4 between 10 and 30 atm. The maximum carbon conversion to soot is approximately 6.5 % at 30 atm and remained constant at higher pressures.
Download or read book High pressure Soot Formation and Diffusion Flame Extinction Characteristics of Gaseous and Liquid Fuels written by Ahmet Emre Karatas and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conjugate Heat Transfer and Sooting Propensity of Ethanol for Laminar Coflow Diffusion Flames at Elevated Pressures written by Wasi Syed and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of sooting propensity of various compositions of methane and ethanol fuel in laminar diffusion flames at elevated pressures was analyzed numerically. Simulations of laminar diffusion flames comprised of pressure conditions up to 20 atm and composition of ethanol and methane fuel ranging from pure methane to pure ethanol. For all fuel compositions evaluated, the total carbon mass flow rate was maintained at a constant value of 0.458 mg/s. Soot formation and soot yield were corroborated against measured data and demonstrated well agreement with trends for pressure and fuel composition. For elevated pressure, fuel compositions with higher ethanol content yield higher peak soot concentrations, however at lower pressures synergistic effects result to soot concentration decreasing with ethanol content for ethanol dominant fuel mixtures. Finally, the effect of conjugate heat transfer and modification in burner wall geometry were evaluated which exhibited improved trends and overall results.
Download or read book Oxygen Enhanced Combustion written by Charles E. Baukal Jr. and published by CRC Press. This book was released on 2013-03-15 with total page 779 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combustion technology has traditionally been dominated by air/fuel combustion. However, two developments have increased the significance of oxygen-enhanced combustion-new technologies that produce oxygen less expensively and the increased importance of environmental regulations. Advantages of oxygen-enhanced combustion include less pollutant emissi
Download or read book Soot Fformation in Co flow and Counterflow Laminar Diffusion Flames of Fuel Mixtures written by Ahmet Emre Karatas and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the formation process of soot in the flames of even-carbon-numbered fuels, acetylene and its derivatives are suspected to be dominant. The addition of an odd-carbon-numbered fuel into these flames introduces methyl radicals and/or C3 chemistries, which are believed to (de)activate certain chemical pathways towards the production of soot. The resultant soot formation rate of the mixture could be higher than the sum of the respective rates of the mixture components, i.e., synergistic eff ect. In this work, the mixtures of butane isomers, ethylene-butane isomers, and propane-butane isomers were studied on a co-flow and a counterflow burner. Chemical effects were isolated from those of thermal and dilution by mixing isomers and comparing the mixtures including one isomer to those including the counterpart. Line of sight attenuation (LOSA) and laser-light extinction techniques were used for measuring soot volume fraction. The results provide information on synergistic effects in soot formation for the fuels used.
Download or read book Soot Formation in Ethane air Coflow Laminar Diffusion Flames at Elevated Pressures written by Paul Michael Mandatori and published by . This book was released on 2006 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ethane-air laminar coflow non-smoking diffusion flames have been studied at pressures up to 3.34 MPa to determine the effect of pressure on soot formation, flame temperatures and physical flame properties. The spectral soot emission (SSE) diagnostic was used to obtain spatially resolved (both radially and axially) soot volume fraction and soot temperature measurements at pressures of 0.20 to 3.34 MPa. In general, temperature profiles of a given height were found to decrease with increasing pressure. Pressure was found to enhance soot formation with decreased sensitivity as pressures were increased. A power law relation between maximum soot volume fraction and pressure was found to be fvmax & prop;P 2.39 for 0.20 & le; P & le; 1.52 MPa and fvmax & prop;P 1.10 for 1.52 & le; P & le; 3.34 MPa. The integrated line-of-sight soot volume fraction was found to vary as fvline, max & prop;P 2.32 for 0.20 & le; P & le; 0.51 MPa, fvline, max & prop;P 1.44 for 0.51 & le; P & le; 1.52 MPa and fvline, max & prop;P 0.95 for 1.52 & le; P & le; 3.34 MPa. The variation of maximum carbon conversion to soot, as a percentage of the fuel's carbon, was etas, max & prop; P2.23 for 0.20 & le; P & le; 1.13 MPa, etas, max & prop; P1.12 for 0.51 & le; P & le; 1.52 MPa and etas, max & prop; P0.41 for 1.52 & le; P & le; 3.34 MPa. The maximum value of carbon conversion was found to be eta s, max = 27.61% at P = 3.34 MPa.
Download or read book The Effect of Elevated Pressure on Soot Formation in a Laminar Jet Diffusion Flame written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Soot volume fraction (f[subscript sv]) is measured quantitatively in a laminar diffusion flame at elevated pressures up to 25 atmospheres as a function of fuel type in order to gain a better understanding of the effects of pressure on the soot formation process. Methane and ethylene are used as fuels; methane is chosen since it is the simplest hydrocarbon while ethylene represents a larger hydrocarbon with a higher propensity to soot. Soot continues to be of interest because it is a sensitive indicator of the interactions between combustion chemistry and fluid mechanics and a known pollutant. To examine the effects of increased pressure on soot formation, Laser Induced Incandescence (LII) is used to obtain the desired temporally and spatially resolved, instantaneous f[subscript sv] measurements as the pressure is incrementally increased up to 25 atmospheres. The effects of pressure on the physical characteristics of the flame are also observed. A laser light extinction method that accounts for signal trapping and laser attenuation is used for calibration that results in quantitative results. The local peak f[subscript sv] is found to scale with pressure as p[superscript 1.2] for methane and p[superscript 1.7] for ethylene.
Download or read book Soot Formation in Non premixed Laminar Flames at Subcritical and Supercritical Pressures written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental study was conducted using axisymmetric co-flow laminar diffusion flames of methane-air, methane-oxygen and ethylene-air to examine the effect of pressure on soot formation and the structure of the temperature field. A liquid fuel burner was designed and built to observe the sooting behavior of methanol-air and n-heptane-air laminar diffusion flames at elevated pressures up to 50 atm. A non-intrusive, line-of-sight spectral soot emission (SSE) diagnostic technique was used to determine the temperature and the soot volume fraction of methane-air flames up to 60 atm, methane-oxygen flames up to 90 atm and ethylene-air flames up to 35 atm. The physical flame structure of the methane-air and methane-oxygen diffusion flames were characterized over the pressure range of 10 to 100 atm and up to 35 atm for ethylene-air flames. The flame height, marked by the visible soot radiation emission, remained relatively constant for methane-air and ethylene-air flames over their respected pressure ranges, while the visible flame height for the methane-oxygen flames was reduced by over 50 % between 10 and 100 atm. During methane-air experiments, observations of anomalous occurrence of liquid material formation at 60 atm and above were recorded. The maximum conversion of the carbon in the fuel to soot exhibited a strong power-law dependence on pressure. At pressures 10 to 30 atm, the pressure exponent is approximately 0.73 for methane-air flames. At higher pressures, between 30 and 60 atm, the pressure exponent is approximately 0.33. The maximum fuel carbon conversion to soot is 12.6 % at 60 atm. For methane-oxygen flames, the pressure exponent is approximately 1.2 for pressures between 10 and 40 atm. At pressures between 50 and 70 atm, the pressure exponent is about -3.8 and approximately -12 for 70 to 90 atm. The maximum fuel carbon conversion to soot is 2 % at 40 atm. For ethylene-air flames, the pressure exponent is approximately 1.4 between 10 and 30 atm. The maximu.
Download or read book Fuel Structure and Pressure Effects on the Formation of Soot Particles in Diffusion Flames written by Robert J. Santoro and published by . This book was released on 1990 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies emphasizing the effects of fuel concentration and operating pressure on the formation of soot particles have been conducted in a series of laminar diffusion flames. These experiments have shown that fuel concentration has a measurable effect on the amount of soot formed in the flame. However, a simple, constant proportionality between the fuel concentration and soot volume fraction has not been found to apply for the range of flow conditions studied. This observation is believed to be a result of flame residence time and diffusion effects which mitigate the consequences of reduced initial fuel concentration. Comparisons with simple laminar diffusion flame models are currently being used to investigate the relationship between initial fuel concentration and local flame concentration fields. Similar studies of soot formation in laminar diffusion flames as a function of operating pressure have also been completed for ethene, ethane and propene fuel species. Keywords: Soot formation, Soot particles, Diffusion flames. (JES).
Download or read book Hydrodynamic Effects on Soot Formation in Laminar Hydrocarbon fueled Diffusion Flames written by Guozheng Lin and published by . This book was released on 1996 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soot Formation in Laminar Diffusion Flames of Gas Mixtures written by Margaret Kathleen Bohan and published by . This book was released on 2006 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the factors that effect soot formation is essential to development of predictive models and the design of combustion processes that reduce the formation of particulates. Synergistic effects in flames of gas mixtures, increases in soot volume fraction that are higher than would be expected based on the soot volume fractions in the pure gas flames, have been observed in previous studies. The two isomers of butane were chosen to eliminate changes in flame carbon content, mass flow rate, and adiabatic flame temperature that are normally encountered when comparing flames of pure gases to flames of gas mixtures, and which also effect soot formation. A co-flow annular burner and a line-of-sight attenuation apparatus were used to produce radially-resolved soot volume fraction measurements. The experimental results give further insight into the sooting propensities of isobutane and n-butane, as well as their effect soot formation in ethylene and methane flames.
Download or read book Application and Comparison of FPI SLFM and FPV Chemistry Tabulation to the Prediction of Soot Formation in Laminar Diffusion Flames at Elevated Pressures written by Marthinus Christoffel Stander de Beer and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical methods to predict soot formation often rely on the use of large detailed chemical mechanisms that can make the numerical simulations very computationally expensive. This study aims to address this issue by employing several chemistry tabulation methods and assessing their capabilities when applied to the prediction of soot in laminar coflow diffusion flames. The tabulation methods considered herein include: the flame-prolongation of intrinsic low dimensional manifold (FPI) method, the steady laminar flamelet method (SLFM), and the flamelet/progress variable (FPV) method. Various techniques for coupling the tabulation methods to soot models are investigated. Flames involving pure methane, and methane/ethanol fuel mixtures are evaluated at both 1 and 4 atm, and a Jet-A surrogate fuelled flame is tested at 1 atm. The tabulation methods are compared to results obtained using the full detailed chemical mechanisms and to experimental results. The relative strengths and weaknesses of the various tabulation methods are discussed.
Download or read book Effects of Fuel Preheat on Soot Formation in 1 G and 0 G Laminar Diffusion Flames written by Bogdan Konsur and published by . This book was released on 1997 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
