Journal articles: 'Kinetic of combustion'

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Qin, Yuelin, Qingfeng Ling, Wenchao He, Jinglan Hu, and Xin Li. "Metallurgical Coke Combustion with Different Reactivity under Nonisothermal Conditions: A Kinetic Study." Materials 15, no. 3 (January 27, 2022): 987. http://dx.doi.org/10.3390/ma15030987.

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The combustion characteristics and kinetics of high- and low-reactivity metallurgical cokes in an air atmosphere were studied by thermogravimetric instrument. The Coats–Redfern, FWO, and Vyazovkin integral methods were used to analyze the kinetics of the cokes, and the kinetic parameters of high- and low-reactivity metallurgical cokes were compared. The results show that the heating rate affected the comprehensive combustion index and combustion reaction temperature range of the cokes. The ignition temperature, burnout temperature, combustion characteristics, and maximum weight-loss rate of low-reactivity coke (L-Coke) were better than high-reactivity coke (H-Coke). Low-reactivity coke had better thermal stability and combustion characteristics. At the same time, it was calculated via three kinetic analysis methods that the combustion activation energy gradually decreased with the progress of the reaction. The coke combustion activation energy calculated by the Coats–Redfern method was larger than the coke combustion activation energy calculated by the FWO and Vyazovkin methods, but the laws were consistent. The activation energy of L-Coke was about 4~8 kJ/mol more than that of H-Coke.

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Zhang, Yong Feng, Xiang Yun Chen, Quan Zhou, Qian Cheng Zhang, and Chun Ping Li. "Combustion Kinetic Analysis of Lignite in Different Oxygen Concentration." Advanced Materials Research 884-885 (January 2014): 37–40. http://dx.doi.org/10.4028/www.scientific.net/amr.884-885.37.

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Combustion behavior of indigenous lignite in oxygen-enriched conditions was investigated by using thermogravimetric analyzer (TGA). Combustion tests were carried out in different oxygen concentration (21%O2/79%N2, 30%O2/70%N2, 40%O2/60%N2, 50%O2/50%N2, 60%O2/40%N2, 70%O2/30%N2). Then get the characteristic temperatures. . The model-fitting mathematical approach was used to evaluated the kinetic triplet (f (α),E,A) through Gorbatchev method. The combustion stages were divided into the early combustion stage and the later combustion stage. The calculation showed that the kinetics parameters higher in the early combustion stage than that in the later combustion stage.

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Oo, Chit Wityi, Masahiro Shioji, Hiroshi Kawanabe, Susan A. Roces, and Nathaniel P. Dugos. "A Skeletal Kinetic Model For Biodiesel Fuels Surrogate Blend Under Diesel-Engine Conditions." ASEAN Journal of Chemical Engineering 15, no. 1 (October 1, 2015): 52. http://dx.doi.org/10.22146/ajche.49693.

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The biodiesel surrogate fuels are realistic kinetic tools to study the combustion of actual biodiesel fuels in diesel engines. The knowledge of fuel chemistry aids in the development of combustion modeling. In order to numerically simulate the diesel combustion, it is necessary to construct a compact reaction model for describing the chemical reaction. This study developed a skeletal kinetic model of methyl decanoate (MD) and n-heptane as a biodiesel surrogate blend for the chemical combustion reactions. The skeletal kinetic model is simply composed of 45 chemical species and 74 reactions based on the full kinetic models which have been developed by Lawrance Livermore National Laboratory (LLNL) and Knowledge-basing Utilities for Complex Reaction Systems (KUCRS) under the diesel like engine conditions. The model in this study is generated by using CHEMKIN and then it is used to produce the ignition delay data and the related chemical species. The model predicted good reasonable agreement for the ignition delays and most of the reaction products at various conditions. The chemical species are well reproduced by this skeletal kinetic model while the good temperature dependency is found under constant pressure conditions 2MPa and 4MPa. The ignition delay time of present model is slightly shorter than the full kinetic model near negative temperature coefficient (NTC) regime. This skeletal model can provide the chemical kinetics to apply in the simulation codes for diesel-engine combustion.

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Zhu, Zhouyuan, Canhua Liu, Yajing Chen, Yuning Gong, Yang Song, and Junshi Tang. "In-situ Combustion Simulation from Laboratory to Field Scale." Geofluids 2021 (December 14, 2021): 1–12. http://dx.doi.org/10.1155/2021/8153583.

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In-situ combustion simulation from laboratory to field scale has always been challenging, due to difficulties in deciding the reaction model and Arrhenius kinetics parameters, together with erroneous results observed in simulations when using large-sized grid blocks. We present a workflow of successful simulation of heavy oil in-situ combustion process from laboratory to field scale. We choose the ongoing PetroChina Liaohe D block in-situ combustion project as a case of study. First, we conduct kinetic cell (ramped temperature oxidation) experiments, establish a suitable kinetic reaction model, and perform corresponding history match to obtain Arrhenius kinetics parameters. Second, combustion tube experiments are conducted and history matched to further determine other simulation parameters and to determine the fuel amount per unit reservoir volume. Third, we upscale the Arrhenius kinetics to the upscaled reaction model for field-scale simulations. The upscaled reaction model shows consistent results with different grid sizes. Finally, field-scale simulation forecast is conducted for the D block in-situ combustion process using computationally affordable grid sizes. In conclusion, this work demonstrates the practical workflow for predictive simulation of in-situ combustion from laboratory to field scale for a major project in China.

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Sun, Minmin, Jianliang Zhang, Kejiang Li, Guangwei Wang, Haiyang Wang, and Qi Wang. "Thermal and kinetic analysis on the co-combustion behaviors of anthracite and PVC." Metallurgical Research & Technology 115, no. 4 (2018): 411. http://dx.doi.org/10.1051/metal/2018064.

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The co-combustion characteristics of anthracite and PVC were investigated by thermogravimetric analysis to study its application in BF. First, the combustion characteristics were investigated. It was found the initial combustion temperature (Ti) of blends decreased with the increase of PVC ratio, while its decreasing rate reached maximum when 10% PVC. Aiming for further characterizing the combustion kinetics, ten gas-solid reaction mechanism functions were adopted for different groups. Results showed that Dimensional Diffusion Model is the best model to describe the combustion kinetics of anthracite and PVC. With this model, combustion kinetic parameters were calculated at 5 °C/min, and the Ea decreases with the addition of PVC. Kinetics compensation effect between the Ea and A was also observed. By Fourier Transform Infrared Spectroscopy (FTIR) analysis, significant differences of elements and functional groups were observed. This study provides theoretical guidance for the utilization of PVC as alternative fuels for BF ironmaking.

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Dinde, Prashant, A. Rajasekaran, and V. Babu. "3D numerical simulation of the supersonic combustion of H2." Aeronautical Journal 110, no. 1114 (December 2006): 773–82. http://dx.doi.org/10.1017/s0001924000001640.

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Results from numerical simulations of supersonic combustion of H2 are presented. The combustor has a single stage fuel injection parallel to the main flow from the base of a wedge. The simulations have been performed using FLUENT. Realisable k-ε model has been used for modelling turbulence and single step finite rate chemistry has been used for modelling the H2-Air kinetics. All the numerical solutions have been obtained on grids with average value for wall y+ less than 40. Numerically predicted profiles of static pressure, axial velocity, turbulent kinetic energy and static temperature for both non-reacting as well as reacting flows are compared with the experimental data. The RANS calculations are able to predict the mean and fluctuating quantities reasonably well in most regions of the flow field. However, the single step kinetics predicts heat release much more rapid than what was seen in the experiments. Nonetheless, the overall pressure rise in the combustor due to combustion is predicted well. Also, the k-ε model is not able to predict the fluctuating quantities in the base region of the wedge where there is strong anisotropy in the presence of combustion.

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Gutierrez, Albio D., and Luis F. Alvarez. "Simulation of Plasma Assisted Supersonic Combustion over a Flat Wall." Mathematical Modelling of Engineering Problems 9, no. 4 (August 31, 2022): 862–72. http://dx.doi.org/10.18280/mmep.090402.

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This work presents a simplified methodology to couple the physics of a nanosecond pulsed discharge to the process of supersonic combustion in a flat wall combustor configuration. Plasma and supersonic combustion are separately simulated and then coupled by seeding plasma-generated radicals on the combustion domain. The plasma model is built assuming spatial uniformity and considering only the kinetic effects of the nanosecond pulsed discharge. Therefore, a zero-dimensional kinetic scheme accounting for the generation of plasma species is utilized. For the combustion model, the complete set of Favre-averaged compressible Navier Stokes equations along with finite rate chemistry is solved through a control-volume based technique via the commercial software Ansys Fluent. The computational results are compared against experimental studies showing that the proposed methodology can capture the main kinetic effects of the nanosecond pulsed discharge on supersonic combustion. OH concentration contours reveal the presence of an enhanced flame when the plasma is applied following the trends from experimental OH PLIF images. In addition, time evolving temperature and OH concentration contours show that the ignition delay time is reduced with the application of the discharge.

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Komarov, Ivan, Daria Kharlamova, Bulat Makhmutov, Sofia Shabalova, and Ilya Kaplanovich. "Natural Gas-Oxygen Combustion in a Super-Critical Carbon Dioxide Gas Turbine Combustor." E3S Web of Conferences 178 (2020): 01027. http://dx.doi.org/10.1051/e3sconf/202017801027.

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The paper presents results for chemical kinetics of combustion process in the combustor of oxy-fuel cycle super-critical carbon dioxide gas turbine based on the Allam thermodynamic cycle. The work shows deviation of the normal flame propagation velocity for the case of transition from the traditional natural gas combustion in the N2 diluent environment to the combustion at super-high pressure up to 300 bar in CO2 diluent. The chemical kinetics parametric study involved the Chemkin code with the GRI-Mesh 3.0 kinetic mechanism. This mechanism provides good correspondence between calculation results and test data. The CO2 and N2 diluents temperature, pressure and contents influence the flame propagation velocity and the chemical kinetics parameters in the two gas turbine types. It is demonstrated that the CO2 diluent slows down chemical reactions stronger than the N2 one. The flame propagation velocity in carbon dioxide is four time smaller than in the N2 one. In the oxy-fuel cycle combustor a pressure increase reduces the flame propagation velocity. Increase of the CO2 content from 60 to 79% reduces the flame propagation velocity for 65% at atmospheric pressure and for 94% at super-critical pressure. An increase of the combustor inlet mixture temperature from 300 to 1100 K at super-critical pressure causes the flame propagation velocity increase for 94%. The flame propagation velocities compatible with the traditional gas turbines may be reached at the CO2 diluent content of the O2 + CO2 mixture in the active combustion zone must be below 50%.

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Zhang, Yong-Feng, Xiang-Yun Chen, Qian-Cheng Zhang, Chun-Ping Li, and Quan Zhou. "Oxygen-enriched combustion of lignite." Thermal Science 19, no. 4 (2015): 1389–92. http://dx.doi.org/10.2298/tsci1504389z.

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The study is concerned on the oxygen-enriched combustion kinetics of lignite. Thermogravimetric experiments were carried out in a thermogravimetric analyzer under O2/N2 conditions, and operated at different heating rates ranging from 5?C per minute to 25?C per minute. Flynn-Wall-Ozawa method was used to calculate the kinetic parameter. The value of activation energy increased when the oxygen concentration varied from 21% to 70%.

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Várhegyi, Gábor, Zoltán Sebestyén, Zsuzsanna Czégény, Ferenc Lezsovits, and Sándor Könczöl. "Combustion Kinetics of Biomass Materials in the Kinetic Regime." Energy & Fuels 26, no. 2 (December 23, 2011): 1323–35. http://dx.doi.org/10.1021/ef201497k.

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Jia, Guohai. "Combustion Characteristics and Kinetic Analysis of Biomass Pellet Fuel Using Thermogravimetric Analysis." Processes 9, no. 5 (May 14, 2021): 868. http://dx.doi.org/10.3390/pr9050868.

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Biomass pellet fuel is one of the development directions of renewable energy. The purpose of the article is to study the combustion characteristics of five kinds of biomass pellet fuel that can be used as biomass fuel and analyze their combustion kinetics. The thermogravimetric method (TG method) was used to analyze the combustion characteristics of five kinds of biomass pellet fuel and to calculate the index S of comprehensive combustion characteristic. The Arrhenius equation and the Coats–Redfern method were used to analyze the combustion kinetics of five kinds of biomass pellet fuel. The activation energy and pre-exponential factor were obtained according to different temperature ranges. Conclusions are as follows: The pyrolysis of five kinds of biomass pellet fuel mainly includes three stages: (1) water evaporation stage, (2) volatile component combustion stage, (3) fixed carbon oxidation stage. The TG curves of five kinds of biomass pellet fuel are roughly the same at the same heating rate. The peaks of thermal weight loss rate and maximum degradation rate are both in the high temperature range. The differential thermal gravity (DTG) curves of five kinds of biomass pellet fuel have an obvious peak. The peak temperature of the largest peak in the DTG curves is 280–310 °C. The first-order reaction equation is used to obtain the kinetic parameters in stages. The correlation coefficients are bigger than the value of 0.92. The fitting results are in good agreement with the experimental results. The activation energy of each sample is basically the same in each stage. The value in the volatile matter combustion stage is 56–542 kJ/mol, and the activation energy of the carbon layer slowly increases rapidly. The five kinds of biomass pellet fuels have good combustion characteristics and kinetic characteristics, and they can be promoted and applied as biomass pellet fuels in the future.

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Nissen, Anna, Zhouyuan Zhu, Anthony Kovscek, Louis Castanier, and Margot Gerritsen. "Upscaling Kinetics for Field-Scale In-Situ-Combustion Simulation." SPE Reservoir Evaluation & Engineering 18, no. 02 (April 23, 2015): 158–70. http://dx.doi.org/10.2118/174093-pa.

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Summary We demonstrate the effectiveness of a non-Arrhenius kinetic upscaling approach for in-situ-combustion processes, first discussed by Kovscek et al. (2013). Arrhenius reaction terms are replaced with equivalent source terms that are determined by a work flow integrating both laboratory experiments and high-fidelity numerical simulations. The new formulation alleviates both stiffness and grid dependencies of the traditional Arrhenius approach. Consequently, the computational efficiency and robustness of simulations are improved significantly. In this paper, we thoroughly investigate the performance of the non-Arrhenius upscaling method compared with Arrhenius kinetics. We investigate robustness by considering grid effects and sensitivity to heterogeneity. Performance improvements of the new kinetic upscaling approach compared with traditional Arrhenius kinetics are demonstrated through numerical experiments in one and two dimensions for both homogeneous- and heterogeneous-permeability fields.

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Zhang, Lin Hai, Deng Qin Xue, Jia Xi Zhang, Yu Fu, and Shu Lin Hou. "Straw Mixed Combustion Characteristics and Kinetic Analysis." Applied Mechanics and Materials 448-453 (October 2013): 1605–11. http://dx.doi.org/10.4028/www.scientific.net/amm.448-453.1605.

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The mixed materials come from Beijing Daxing District, corn stalks as the main raw material, peanut shells and wheat straw as affixation. Combustion characteristics of mixed materials are studied by using Thermogravimetric analyzer and combustion dynamics studied by using Coats-Refern method to offer practical and theoretical data for crop straw combustion and Densified . Studies have shown that Combustion curve of three samples have two distinct peaks, divided into water evaporated to dryness, and the combustion of volatiles, fixed carbon combustion and burnout four basic stages and lied a larger overlapping area in the entire combustion stage, That combustion characteristics and kinetic parameters of mixed materials are influenced by adding peanut shells, and less affected on adding wheat straws.

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Stolarek, P., and S. Ledakowicz. "Thermal processing of sewage sludge by drying, pyrolysis, gasification and combustion." Water Science and Technology 44, no. 10 (November 1, 2001): 333–39. http://dx.doi.org/10.2166/wst.2001.0655.

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Thermal processing of sewage sludge including drying, pyrolysis and gasification or combustion may be an alternative to other ways of utilising it. In this paper thermogravimetric analysis (TGA) was employed in the investigation of thermal decomposition of sewage sludge. The kinetic parameters of drying, pyrolysis and gasification or combustion of sewage sludge have been determined in an inert-gas (argon) and additionally some series of the sludge decomposition experiments have been carried out in air, in order to compare pyrolysis and combustion. The pyrolysis char has been gasified with carbon dioxide. A typical approach to the kinetics of thermal decomposition of a solid waste is to divide the volatile evolution into a few fractions (lumps), each of which is represented by a single first-order reaction. If these lumps are assumed to be non-interacting and evolved by independent parallel reactions the first-order kinetic parameters such as activation energy Ei and pre-exponential factor Ai can be determined from mathematical evaluation of TG or DTG curves. The object of our investigations was a municipal sludge from the two wastewater treatment plants (WTP) in Poland. The experiments have been carried out in the thermobalance Mettler-Toledo type TGA/SDTA851 LF, in the temperature range 30-1,000°C. Five different values of heating rate have been applied β = 2, 5, 10, 15 and 20 K/min. The values of Ei and Ai have been determined for all recognised lumps of gaseous products. The method employed has also revealed its usefulness for the determination of kinetic parameters for municipal sludge, that possess an undefined content. An alternative route to combustion of sewage sludge is its gasification, which significantly increases the gaseous product (pyrolytic gas + syngas). Besides pyrolysis kinetics, gasification or combustion process kinetics have also been determined.

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Meng, Kang, Wang Sheng Chen, Ying Zhang, Jun Han, and Xing Dong Wang. "Investigation of Vanadium Containing Shale in Combustion Behavior." Advanced Materials Research 634-638 (January 2013): 775–82. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.775.

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The combustion kinetics and characteristics of vanadium containing shale were studied in a thermogravimetric analyzer and drop tube furnace. The results indicate that vanadium containing shale has a high ignition temperature and a poor stable-combustion characteristic. At the same time, it is found that the optimum reaction temperature of de-carbon is 1273 K. Moreover, the kinetic parameters are calculated by isoconversional method at different reaction stages.

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Banu, Ionut, Mihaela Manta, Ioana Stoica, Georgeta Bercaru, and Grigore Bozga. "Kinetics of methyl methacrylate combustion over a Pt/alumina catalyst." Journal of the Serbian Chemical Society 83, no. 6 (2018): 759–72. http://dx.doi.org/10.2298/jsc170809008b.

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The combustion of methyl methacrylate (MMA) over a commercial Pt/?-alumina catalyst was investigated, in the lean air mixtures specific for the depollution applications. The experiments were performed at temperatures between 150 and 360?C, with MMA concentrations of 460 to 800 ppmv and the gas flow rates between 200 and 300 mL min-1. The results evidenced a negative influence of MMA concentration on the combustion kinetics. A kinetic model of the combustion process was developed, based on the Langmuir?Hinshelwood mechanism, assuming the surface reaction between adsorbed oxygen atoms and adsorbed MMA molecules as the controlling step. The rate expression included the inhibition effects of MMA and water adsorption on the process kinetics. The MMA combustion process simulations evidenced the significant influences of the bulk gas to catalyst particle mass transfer, on the overall kinetics.

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Peters, Bernhard, and Joanna Smuła-Ostaszewska. "A Numerical Approach to Predict Sulphur Dioxide Emissions During Switchgrass Combustion." Chemical and Process Engineering 34, no. 1 (March 1, 2013): 121–37. http://dx.doi.org/10.2478/cpe-2013-0011.

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Abstract The demand for a net reduction of carbon dioxide and restrictions on energy efficiency make thermal conversion of biomass a very attractive alternative for energy production. However, sulphur dioxide emissions are of major environmental concern and may lead to an increased corrosion rate of boilers in the absence of sulfatation reactions. Therefore, the objective of the present study is to evaluate the kinetics of formation of sulphur dioxide during switchgrass combustion. Experimental data that records the combustion process and the emission formation versus time, carried out by the National Renewable Energy Institute in Colorado (US), was used to evaluate the kinetic data. The combustion of switchgrass is described sufficiently accurate by the Discrete Particle Method (DPM). It predicts all major processes such as heating-up, pyrolysis, combustion of switchgrass by solving the differential conservation equations for mass and energy. The formation reactions of sulphur dioxide are approximated by an Arrhenius-like expression including a pre-exponential factor and an activation energy. Thus, the results predicted by the Discrete Particle Method were compared to measurements and the kinetic parameters were subsequently corrected by the least square method until the deviation between measurements and predictions was minimised. The determined kinetic data yielded good agreement between experimental data and predictions.

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Kukshinov, N. V., S. N. Batura, and M. S. Frantsuzov. "Validation of Methods for Calculating Hydrogen Combustion in a Supersonic Model Air Flow Using the Experimental Data of Beach — Evans — Schexnayder." Proceedings of Higher Educational Institutions. Маchine Building, no. 11 (716) (November 2019): 36–45. http://dx.doi.org/10.18698/0536-1044-2019-11-36-45.

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This paper deals with numerical simulation of combustion of a hydrogen-air mixture in a supersonic flow. The simulation is based on solving the complete system of Navier-Stokes equations with closure using the turbulence model and detailed chemical kinetics. The mixing and combustion of a hydrogen-air fuel mixture is considered in the experimental formulation of Beach-Evans-Schexnayder. The effect of various kinetic mechanisms, turbulence models, TCI models, and boundary conditions on the solution is studied qualitatively and quantitatively. The relative errors of mass concentration of water for control sections are determined, and the methods’ boundaries are shown. Conclusions are drawn on the influence of turbulent mixing mechanisms and chemical kinetics on the combustion of hydrogen.

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Branca, Carmen, and Colomba Di Blasi. "Combustion Kinetics of Secondary Biomass Chars in the Kinetic Regime." Energy & Fuels 24, no. 10 (October 21, 2010): 5741–50. http://dx.doi.org/10.1021/ef100952x.

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Cinar, Murat, Berna Hasçakir, Louis M. Castanier, and Anthony R. Kovscek. "Predictability of Crude Oil In-Situ Combustion by the Isoconversional Kinetic Approach." SPE Journal 16, no. 03 (June 16, 2011): 537–47. http://dx.doi.org/10.2118/148088-pa.

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Summary One method to access unconventional heavy-crude-oil resources as well as residual oil after conventional recovery operations is to apply in-situ combustion (ISC) enhanced oil recovery. ISC oxidizes in place a small fraction of the hydrocarbon, thereby providing heat to reduce oil viscosity and increase reservoir pressure. Both effects serve to enhance recovery. The complex nature of petroleum as a multicomponent mixture and the multistep character of combustion reactions substantially complicate analysis of crude-oil oxidation and the identification of settings where ISC could be successful. In this study, isoconversional analysis of ramped temperature-oxidation (RTO) kinetic data was applied to eight different crude-oil samples. In addition, combustion-tube runs that explore ignition and combustion-front propagation were carried out. By using experimentally determined combustion kinetics of eight crude-oil samples along with combustion-tube results, we show that isoconversional analysis of RTO data is useful to predict combustion-front propagation. Isoconversional analysis also provides new insight into the nature of the reactions occurring during ISC. Additionally, five of the 10 crude-oil/rock systems studied employed a carbonate rock. No system displayed excessive oxygen consumption resulting from carbonate decomposition at combustion temperatures. This result is encouraging as it contributes to widening of the applicability of ISC.

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Pawlaczyk, Anna, and Krzysztof J. Gosiewski. "Simplified Kinetic Model for Thermal Combustion of Lean Methane–Air Mixtures in a Wide Range of Temperatures." International Journal of Chemical Reactor Engineering 11, no. 1 (June 18, 2013): 111–21. http://dx.doi.org/10.1515/ijcre-2012-0074.

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Abstract The paper presents results of kinetic studies on thermal methane combustion over honeycomb monoliths. An analysis of the previous experiments [1] has shown that equations proposed there and their kinetic parameters satisfactorily describe kinetics only for relatively low temperatures up to approx. 700°C. The present study corresponds to that related and supplements the previous data with new kinetic parameters obtained in higher temperatures in the reaction zone up to 900°C. A method of the reaction rate calculation for further simulation studies combining the kinetic parameters obtained in both ranges of low (LT) according to Gosiewski et al. [1] and high temperatures (HT) are also presented in the paper.

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He, Zhan Wen, and Chuan Cheng Zhang. "Study on Combustion Characteristics of Impurity Coal Based on TG-DTG-DTA." Advanced Materials Research 568 (September 2012): 360–63. http://dx.doi.org/10.4028/www.scientific.net/amr.568.360.

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Abstract.Based on TG-DTG-DTA, combustion characteristics and kinetic parameters of impure coal in the 10 °C / min heating rate were studied. The results showed that with the increase in the proportion of impurities, ignition temperature, burned temperature significantly improved; combustion characteristics of index clearly decreased; combustion process can be described by a diffusion kinetic equation

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MIYOSHI, Akira. "Combustion Kinetic Modeling -- toward the Innovation of Internal Combustion Engine." Proceedings of Mechanical Engineering Congress, Japan 2017 (2017): W071001. http://dx.doi.org/10.1299/jsmemecj.2017.w071001.

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Wang, Qing, Xu Dong Wang, Hong Peng Liu, and Chun Xia Jia. "Co-Combustion Mechanism Analysis of Oil Shale Semi-Coke and Rice Straws Blends." Advanced Materials Research 614-615 (December 2012): 45–48. http://dx.doi.org/10.4028/www.scientific.net/amr.614-615.45.

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In this work, a series of combustion experiments for oil shale semi-coke , rice straws as well as their mixture were conducted by the thermogravimetric analyzer at different heating rates (10, 20 and 50 K/min) under atmospheric pressure. Combustion characteristic curves and combustion characteristic parameters were acquired. The results showed that the combustion process of blends can be broadly separated into three stages: combustion of the volatile matter, combustion of fixed carbon and combustion of difficult decomposition substance. The point of ignition and burnout shifted to higher temperature with increasing the heating rates. Furthermore, kinetics parameters were analyzed in the second stage. The result showed feasibility of using the reaction model to solve the kinetic parameters of biomass combustion. Finally, the obtained DTG curves were separated by Gaussian Fitting method. The result showed that the derivative thermogravimetry (DTG) curve displays an overlapping peak consisted of three sub-peaks at 645–900K under heating rate of 20K/min.

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Liu, Xiaorui, Dong Li, Jiamin Yang, and Longji Yuan. "Kinetic Mechanisms and Emissions Investigation of Torrefied Pine Sawdust Utilized as Solid Fuel by Isothermal and Non-Isothermal Experiments." Materials 15, no. 23 (December 4, 2022): 8650. http://dx.doi.org/10.3390/ma15238650.

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This study comprehensively investigated the utilization of torrefied pine sawdust (PS) as solid fuels, involving the characterization of torrefied PS properties, the investigation of combustion behaviors and kinetic mechanisms by non-isothermal experiments, and the evaluation of emissions during isothermal experiments. Results show that torrefaction significantly improved the quality of the solids. The upgradation of torrefied PS properties then further enhanced its combustion performance. For the kinetics mechanisms, degradation mechanisms and diffusion mechanisms were respectively determined for the volatile combustion and the char combustion by using both Coats–Redfern (CR) and Freeman–Carroll (FC) methods. Further, after torrefaction, the emission of NO for volatile combustion reduced while it increased for char combustion. An inverse relationship was found between the conversion of fuel-N to NO and the nitrogen content in the torrefied samples. This study provided comprehensive insights for considering torrefaction as a pretreatment technique for PS utilization as a solid fuel.

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SHIMIZU, Taito, and Tamio IDA. "Combustion kinetic analysis of torrefied biocoke." Proceedings of the Symposium on Environmental Engineering 2021.31 (2021): 206. http://dx.doi.org/10.1299/jsmeenv.2021.31.206.

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Gerasimov, G. Ya, Yu V. Tunik, P. V. Kozlov, V. Yu Levashov, I. E. Zabelinskii, and N. G. Bykova. "Simplified Kinetic Model of Kerosene Combustion." Russian Journal of Physical Chemistry B 15, no. 4 (July 2021): 637–44. http://dx.doi.org/10.1134/s1990793121040163.

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Baulch, D. L., C. J. Cobos, R. A. Cox, C. Esser, P. Frank, Th Just, J. A. Kerr, et al. "Evaluated Kinetic Data for Combustion Modelling." Journal of Physical and Chemical Reference Data 21, no. 3 (May 1992): 411–734. http://dx.doi.org/10.1063/1.555908.

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Frassoldati, Alessio, Alberto Cuoci, Alessandro Stagni, Tiziano Faravelli, and Eliseo Ranzi. "Skeletal kinetic mechanism for diesel combustion." Combustion Theory and Modelling 21, no. 1 (September 1, 2016): 79–92. http://dx.doi.org/10.1080/13647830.2016.1222082.

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LINDSTEDT, R. P., and L. Q. MAURICE. "Detailed Kinetic Modelling of Toluene Combustion." Combustion Science and Technology 120, no. 1-6 (November 1996): 119–67. http://dx.doi.org/10.1080/00102209608935571.

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Boukhalfa, Nora. "Chemical Kinetic Modeling of Methane Combustion." Procedia Engineering 148 (2016): 1130–36. http://dx.doi.org/10.1016/j.proeng.2016.06.561.

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Benson, Sidney W. "Combustion, a chemical and kinetic view." Symposium (International) on Combustion 21, no. 1 (January 1988): 703–11. http://dx.doi.org/10.1016/s0082-0784(88)80302-3.

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Lindstedt, R. P. "The modelling of direct chemical kinetic effects in turbulent flames." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 214, no. 3 (March 1, 2000): 177–89. http://dx.doi.org/10.1243/0954410001531999.

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Combustion chemistry-related effects have traditionally been of secondary importance in the design of gas turbine combustors. However, the need to deal with issues such as flame stability, relight and pollutant emissions has served to bring chemical kinetics and the coupling of finite rate chemistry with turbulent flow fields to the centre of combustor design. Indeed, improved cycle efficiency and more stringent environmental legislation, as defined by the ICAO, are current key motivators in combustor design. Furthermore, lean premixed prevaporized (LPP) combustion systems, increasingly used for power generation, often operate close to the lean blow-off limit and are prone to extinction/reignition type phenomena. Thus, current key design issues require that direct chemical kinetic effects be accounted for accurately in any simulation procedure. The transported probability density function (PDF) approach uniquely offers the potential of facilitating the accurate modelling of such effects. The present paper thus assesses the ability of this technique to model kinetically controlled phenomena, such as carbon monoxide emissions and flame blow-off, through the application of a transported PDF method closed at the joint scalar level. The closure for the velocity field is at the second moment level, and a key feature of the present work is the use of comprehensive chemical kinetic mechanisms. The latter are derived from recent work by Lindstedt and co-workers that has resulted in a compact 141 reactions and 28 species mechanism for LNG combustion. The systematically reduced form used here features 14 independent C/H/O scalars, with the remaining species incorporated via steady state approximations. Computations have been performed for hydrogen/carbon dioxide and methane flames. The former (high Reynolds number) flames permit an assessment of the modelling of flame blow-off, and the methane flame has been selected to obtain an indication of the influence of differential diffusion effects among gaseous species. The agreement with experimental data is excellent. The predicted blow-off, velocity is within 10 per cent of the experimental value and it is further shown that experimental levels of major and minor species are well reproduced. Interestingly, comparisons of experimental data with prediction indicate only a modest influence of differential diffusion effects on gaseous species. A comparison with previous modelling efforts, featuring smaller scalar spaces, permits the conclusion that accurate chemistry is a prerequisite for quantitative predications of finite rate chemical kinetic effects.

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Li, Wen Yan, Xing Lei Liu, Qiu Luan Chen, and Feng Ming Chu. "The Performance Research on Reaction of Fe₂O₃/Al₂O₃ Oxygen Carrier and CO in Chemical-Looping Combustion Process." Advanced Materials Research 550-553 (July 2012): 974–78. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.974.

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Chemical-looping combustion (CLC) is a novel technology, which has inherent property of separating the greenhouse gas CO2, which uses oxygen carriers to transfer oxygen for combustion from air to fuel. The reactivity of Fe2O3/Al2O3 oxygen carrier was assessed by measuring their ability to oxidize CO. The kinetics and mechanism of oxygen carrier have been studied by TG and DTG techniques. The kinetic mechanism function of the reaction between Fe2O3/Al2O3 and CO has been built using the Coats-Redfern equation.

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Maspanov, Sergej, Igor Bogov, Alexander Smirnov, Svetlana Martynenko, and Vladimir Sukhanov. "Analysis of Gas-Turbine Type GT-009 M Low-Toxic Combustion Chamber with Impact Cooling of the Burner Pipe Based on Combustion of Preliminarily Prepared Depleted Air–Fuel Mixture." Energies 15, no. 3 (January 19, 2022): 707. http://dx.doi.org/10.3390/en15030707.

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This article analyzes the mechanism of formation of the main components of harmful emissions characteristic of combustion chambers operating on conventional hydrocarbon fuels. The method of combustion of a preliminarily prepared depleted air–fuel mixture was chosen as the object of the study. This method of suppressing harmful emissions was implemented in the design of a low-toxic combustion chamber developed as applied to the GT-009 M type unit with impact cooling of the burner pipe and provides for stabilization of the main kinetic flame by means of a diffusion-kinetic and a standby burner device. The results of the calculations performed with regard to the operating conditions of the low-toxic combustion chamber at the nominal load of GT-009 M allow us to conclude that the practical use of combustion of a depleted, preprepared, fuel–air mixture in combination with diffusion-kinetic stabilization of combustion is promising. The topic of this article is related to the problem of ecological improvement of gas turbine unit combustion chambers, which determines its utmost importance and relevance.

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Zhang, Yong Feng, Quan Zhou, Chun Ping Li, Jie Bai, and Xiang Yun Chen. "Experiment of Sheng Li Lignite Combustion Kinetics under Oxygen-Enriched Conditions." Advanced Materials Research 838-841 (November 2013): 1949–52. http://dx.doi.org/10.4028/www.scientific.net/amr.838-841.1949.

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The characteristics of Sheng Li (China) Lignite combustion under oxygen-enriched conditions were studied by thermogravimetric analysis , including TGDTG and DTA. Experiments on lignite combustion were carried out under four kinds of oxygen-enriched conditions (O2/N2mixture atmospheres) and with a heating rate of 10°C/min. The experiments of working temperature range was 20°C-900°C. The combustion process, regarded as the first order reaction, was analyzed through the Gorbachev kinetic equation participants, which gained the conclusion that Sheng Li lignite combustion reaction shift to low temperature zone and kinetic parameters of combustion increase gradually when oxygen concentration increase.

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Chen, Junjie, Baofang Liu, Xuhui Gao, and Deguang Xu. "Computational Fluid Dynamics Simulations of Lean Premixed Methane-Air Flame in a Micro-Channel Reactor Using Different Chemical Kinetics." International Journal of Chemical Reactor Engineering 14, no. 5 (October 1, 2016): 1003–15. http://dx.doi.org/10.1515/ijcre-2015-0174.

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Abstract Flame temperature and structure are a useful tool for describing flame dynamics and flame stability, especially at the micro-scale. The objective of this study is to examine the effect of different kinetic models (that have been proven to accurately predict the macro-combustion behavior of hydrocarbons) on the combustion characteristics and the flame stability in microreactors, and to explore the applicability of these kinetic models at the micro-scale. Computational fluid dynamics (CFD) simulations of lean premixed methane-air flame in micro-channel reactors were carried out to examine the effect of different reaction mechanisms (Mantel, Duterque and Fernández-Tarrazo model) on the reaction rate and the flame structure and temperature. The time-scales with regard to homogeneous reaction and heat transfer were analyzed. The CFD results indicate that kinetic models strongly affect flame stability. Large transverse gradients in temperature and species are observed in all kinetic models, despite the small scales of the microreactor. Preheating, combustion, and post-combustion regions can be distinguished only in Duterque and Mantel model. Duterque model causes a stable elongated homogeneous flame with a considerable ignition delay as well as a dead region with cold feed accumulation near the entrance, and is inappropriate for micro-combustion studies because of the seriously overestimated flame temperature. Fernández-Tarrazo model causes a rapid extinction and a flashback risk, and is also inappropriate for micro-combustion studies due to the significantly underestimated reaction rate, without taking all kinetic factors into account. Mantel model can accurately predict the micro-flame behavior and consequently can be used for describing micro-combustion.

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Ambrosi, Grigore. "IGNITION AND COMBUSTION OF SINGLE SOLID PARTICLES AS NON-ISOTHERMAL METHODS OF CHEMICAL KINETICS." Journal of Engineering Science 28, no. 3 (September 2021): 64–70. http://dx.doi.org/10.52326/jes.utm.2021.28(3).04.

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The ignition and combustion of single particles of crystalline boron continue to produce major scientific interest due to the particularities of the process and diversity of potential applications of boron compounds. The full valorization of boron energetic potential is a very current scientific challenge. The objective of the paper is to systematize the methodology for evaluating the kinetic parameters of boron ignition and combustion reactions in various oxidizing gaseous environments. Experimental dependencies between the ignition temperature and the particle size, as well as the combustion time as a function of oxidizing temperature are used for the calculation of the kinetic constants. As a main result, the kinetic parameters of the ignition and combustion reactions of boron in oxygen and water vapor are calculated.

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Fooladgar, Ehsan, and C. K. Chan. "Large Eddy Simulation of a Swirl-Stabilized Pilot Combustor from Conventional to Flameless Mode." Journal of Combustion 2016 (2016): 1–16. http://dx.doi.org/10.1155/2016/8261560.

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This paper investigates flame and flow structure of a swirl-stabilized pilot combustor in conventional, high temperature, and flameless modes by means of a partially stirred reactor combustion model to provide a better insight into designing lean premixed combustion devices with preheating system. Finite rate chemistry combustion model with one step tuned mechanism and large eddy simulation is used to numerically simulate six cases in these modes. Results show that moving towards high temperature mode by increasing the preheating level, the combustor is prone to formation of thermalNOxwith higher risks of flashback. In addition, the flame becomes shorter and thinner with higher turbulent kinetic energies. On the other hand, towards the flameless mode, leaning the preheated mixture leads to almost thermalNOx-free combustion with lower risk of flashback and thicker and longer flames. Simulations also show qualitative agreements with available experiments, indicating that the current combustion model with one step tuned mechanisms is capable of capturing main features of the turbulent flame in a wide range of mixture temperature and equivalence ratios.

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Kong, S. C., and R. D. Reitz. "Use of Detailed Chemical Kinetics to Study HCCI Engine Combustion With Consideration of Turbulent Mixing Effects." Journal of Engineering for Gas Turbines and Power 124, no. 3 (June 19, 2002): 702–7. http://dx.doi.org/10.1115/1.1413766.

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Detailed chemical kinetics was used in an engine CFD code to study the combustion process in HCCI engines. The CHEMKIN code was implemented in KIVA such that the chemistry and flow solutions were coupled. The reaction mechanism consists of hundreds of reactions and species and is derived from fundamental flame chemistry. Effects of turbulent mixing on the reaction rates were also considered. The results show that the present KIVA/CHEMKIN model is able to simulate the ignition and combustion process in three different HCCI engines including a CFR engine and two modified heavy-duty diesel engines. Ignition timings were predicted correctly over a wide range of engine conditions without the need to adjust any kinetic constants. However, it was found that the use of chemical kinetics alone was not sufficient to accurately simulate the overall combustion rate. The effects of turbulent mixing on the reaction rates need to be considered to correctly simulate the combustion and heat release rates.

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Komarov, I. I., D. M. Kharlamova, A. N. Vegera, and V. Y. Naumov. "Study on effect CO2 diluent on fuel cоmbustion in methane-oxygen combustion chambers." Vestnik IGEU, no. 2 (April 30, 2021): 14–22. http://dx.doi.org/10.17588/2072-2672.2021.2.014-022.

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Studying closed gas turbine cycles on supercritical carbon dioxide is currently a promising issue in the development of power energy sector in terms of increasing energy efficiency and minimizing greenhouse gas emissions into the atmosphere. Combustion of methane with oxygen in the combustion chamber occurs not in the nitrogen environment, but in the environment of carbon dioxide, that is the working fluid of the cycle, which is an inhibitor of chemical reactions. A large mass content of such a diluent of the reaction mixture in the volume of the chamber leads to the risks of significant chemical underburning, efficiency decrease of the combustion chamber and the cycle as a whole. The aim of the research is to study the kinetic parameters of the combustion of methane with oxygen in a supercritical CO2 diluent medium to ensure reliable and stable combustion of fuel by assessing the degree of the inhibitory effect of CO2 and determining its permissible amount in the active combustion zone of the combustion chamber. The research method is a numerical simulation of turbulent-kinetic processes of methane combustion in the combustion chamber using the reduced methane combustion mechanism. Ansys Fluent software package has been used. The authers have studied the impact of CO2 diluent on fuel cоmbustion in methane-oxygen combustion chambers. It is found that the combustor flame stabilization takes place if the content of СО2 diluent supplied to the mixture with oxidizer is 0,46–0,5 of mass fraction; additional СО2 diluent forms local low temperature zones which slow down the combustion process. When this happens, adding cooling СО2 into the flame stabilization zone should be eliminated. The study has found that no more than 20 % of the total carbon dioxide content should be supplied to the combustion chamber; to stabilize the flame and reduce its length, it is necessary to install blades to swirl the fuel and oxidizer mixed with CO2 at the inlet of the combustion chamber; CO2 supply for cooling should be carried out not less than 130 mm away from the burner mouth.

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Barysheva, Olga, Renat Sadykov, Yuri Khabibullin, and Elizaveta Zheltukhina. "Forecasting of an output of eco toxicants at thermal decomposition of chemical fuel." E3S Web of Conferences 140 (2019): 08002. http://dx.doi.org/10.1051/e3sconf/201914008002.

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Combustion of high-energy chemical fuels containing chlorine in the element structure can lead to formation in the particles of smoke of super eco toxicants—the polychlorinated dioxins and furans. The numerical experiment conducted was based on solution of the equations of chemical kinetics. The computational and theoretical researches directed to the solution of a problem of determination of parameters of combustion products of chemical fuels taking into account formation of harbingers of the polychlorinated dioxins were executed. The main data on the accepted method of determination of disequilibrium structures of products of burning the chlorine-containing chemical fuels were represented. Based on the analysis of references about mechanisms and speeds of chemical reactions of transformations of chlorine-containing connections, the kinetic model of formation of predecessors of dioxins is constructed. The carried-out calculations showed (assuming chemical balance) that process of formation of dioxins is significantly disequilibrious. The results of kinetic researches on emission of harbingers of dioxins showed the nature of the influence of different components of combustion products of chemical fuels on time for the different levels of temperatures.

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Mai, Tam V. T., Thanh Q. Bui, Nguyen Thi Ai Nhung, Phan Tu Quy, Krishna Prasad Shrestha, Fabian Mauss, Binod Raj Giri, and Lam K. Huynh. "An Ab Initio RRKM-Based Master Equation Study for Kinetics of OH-Initiated Oxidation of 2-Methyltetrahydrofuran and Its Implications in Kinetic Modeling." Energies 16, no. 9 (April 27, 2023): 3730. http://dx.doi.org/10.3390/en16093730.

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Cyclic ethers (CEs) can be promising future biofuel candidates. Most CEs possess physico-chemical and combustion indicators comparable to conventional fuels, making them suitable for internal combustion engines. This work computationally investigates the kinetic behaviors of hydrogen abstraction from 2-methyl tetrahydrofuran (2MTHF), one of the promising CEs, by hydroxyl radicals under combustion and atmospheric relevant conditions. The various reaction pathways were explored using the CCSD(T)/cc-pVTZ//M06-2X/aug-cc-pVTZ level of theory. The Rice–Ramsperger–Kassel–Marcus-based master equation (RRKM-ME) rate model, including treatments for hindered internal rotation and tunneling, was employed to describe time-dependent species profiles and pressure and temperature-dependent rate coefficients. Our kinetic model revealed that the H-abstraction proceeds via an addition-elimination mechanism forming reaction complexes at both the entrance and exit channels. Eight different reaction channels yielding five radical products were located. The reaction exhibited complex kinetics yielding a U-shaped Arrhenius behavior. An unusual occurrence of negative temperature dependence was observed at low temperatures, owing to the negative barrier height for the hydrogen abstraction reaction from the C-H bond at the vicinity of the O-atom. A shift in the reaction mechanism was observed with the dominance of the abstraction at Cα-H of 2MTHF ring (causing negative-T dependence) and at CH3 (positive-T dependence) at low and high temperatures, respectively. Interestingly, the pressure effect was observed at low temperatures, revealing the kinetic significance of the pre-reaction complex. Under atmospheric pressure, our theoretical rate coefficients showed excellent agreement with the available literature data. Our model nicely captured the negative temperature-dependent behaviors at low temperatures. Our predicted global rate coefficients can be expressed as k (T, 760 Torr) = 3.55 × 101 × T−4.72 × exp [−340.0 K/T] + 8.21 × 10−23 × T3.49 × exp [918.8 K/T] (cm3/molecule/s). Our work provides a detailed kinetic picture of the OH-initiated oxidation kinetics of 2MTHF. Hence, this information is useful for building a kinetic me chanism for methylated cyclic ethers.

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Yang, Guisheng, Zhihong Yang, Jinliang Zhang, Zhanhai Yang, and Jiugang Shao. "Combustion Characteristics and Kinetics Study of Pulverized Coal and Semi-Coke." High Temperature Materials and Processes 38, no. 2019 (February 25, 2019): 783–91. http://dx.doi.org/10.1515/htmp-2019-0034.

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AbstractCombustion process of bituminous coal, steam coal, anthracite (AC) and semi-coke were investigated through thermogravimetric analysis method and influence of metamorphic grade as well as heating rate on combustion characteristics were analyzed. Results show that combustion performance could not be represented by single combustion characteristic parameter. Through analysis of comprehensive combustion characteristic indexes, with increase of metamorphic grade combustion performance of coal is lowered, and combustion performance of semi-coke and AC are close to each other. With increase of heating rate, combustion curves move into high temperature region and comprehensive combustion characteristic indexes are increased, which show that the combustion performance is improved. Random pore model (RPM), unreacted shrinking core model (URCM) and volume model were used to calculate kinetic parameters of combustion process. Results show that RPM has the best performance to represent combustion process of the four samples and through calculation by RPM kinetic energy of combustion process for all samples are between 43.08 and 99.43 kJ/mol, and there is compensation effect during combustion process.

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Zhang, Chuan Mei, Jing Jin, Dan Dan He, Hao Zhang, Jie Jiang, Xin Yong Gao, and Wen Jing Gao. "Reaction Mechanism Study on Combustion of Micro Nanometer Iron Powder." Advanced Materials Research 535-537 (June 2012): 459–64. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.459.

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Thermogravimetric curves of micro nanometer iron powder’s combustion were studied in different heating rates that were 10K/min, 20 K/min, 30 K/min and 40 K/min, and the particle sizes of iron were 100nm and 20μm. The iron’s kinetic parameters of combustion reaction were calculated by Coats-Redfern integral, differential and Kissinger methods, then the kinetic model was determined and the most probable mechanism function was verified by Popescu method. The results show that different heating rates, particle sizes and calculations can affect kinetic parameters and reaction mechanism. The activation energy of 100nm and 20μm iron powder’s combustion is 122.48 KJ/mol and 161.64 KJ/mol respectively. The combustion reaction of micro nanometer iron powder is controlled by random nucleation and subsequent growth model which is in agreement with Avrami-Erofeev equation. Rational control for the temperature and reaction time are conducive to optimize the combustion reaction of micro nanometer iron powder.

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Xiang, Dong, and Weihua Zhu. "Mechanisms and kinetics of initial pyrolysis and combustion reactions of 1,1-diamino-2,2-dinitroethylene from density functional tight-binding molecular dynamics simulations." Canadian Journal of Chemistry 97, no. 11 (November 2019): 795–804. http://dx.doi.org/10.1139/cjc-2019-0141.

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The density functional tight-binding molecular dynamics approach was used to study the mechanisms and kinetics of initial pyrolysis and combustion reactions of isolated and multi-molecular FOX-7. Based on the thermal cleavage of bridge bonds, the pyrolysis process of FOX-7 can be divided into three stages. However, the combustion process can be divided into five decomposition stages, which is much more complex than the pyrolysis reactions. The vibrations in the mean temperature contain nodes signifying the formation of new products and thereby the transitions between the various stages in the pyrolysis and combustion processes. Activation energy and pre-exponential factor for the pyrolysis and combustion reactions of FOX-7 were obtained from the kinetic analysis. It is found that the activation energy of its pyrolysis and combustion reactions are very low, making both take place fast. Our simulations provide the first atomic-level look at the full dynamics of the complicated pyrolysis and combustion process of FOX-7.

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Zhang, Jun Jiao, Xu Ming Zhang, Da Long Jiang, Yuan Fang Zhao, Zhi Fei Zhang, Hong Wei Song, Qiang Lu, and Chang Qing Dong. "Research on TG-DTG Analysis and Combustion Kinetics Characteristic of Biomass Fly Ash and Ash." Applied Mechanics and Materials 130-134 (October 2011): 396–400. http://dx.doi.org/10.4028/www.scientific.net/amm.130-134.396.

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The fly ash and ash of different biomass power plants are selected as research objects, of which the combustion characteristics are studied. At the heating rates of 50°C/min, at the final reaction temperature of 900°C, and under the condition of air as carrier gas, weight loss curve and weight loss rate curve are analyzed respectively. TG, DTG curves of fly ash and ash from different power plant are gained, different combustion conditions are studied, and combustion kinetic equations of different biomass fly ash and ash are established, kinetics parameters are obtained by the Coats-Redfern method. Besides, combustion condition and reburning feasibility of different biomass fly ash and ash are analyzed, which provide a theoretical support for biomass power plant operation, such as improving their fuel burn rate.

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Qu, Li Na, Yuan Gang Jiang, and Ru Le Gao. "The Research on the Relationship between the Coal Volatile and the Kinetics Parameters by Thermo-Gravimetric Experiment." Advanced Materials Research 512-515 (May 2012): 1813–18. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.1813.

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Coal spontaneous combustion is a common coal mine disaster, the internal mechanism of coal combustion is revealed better by researched the relationship between the coal volatile and the kinetics parameters. Based on the method of non-isothermal, the coal samples from Jinggezhuang9#, Jinggezhuang11#, Qianjiaying, Tangshan and Tunlan are used the thermo-gravimetric experiment. The relationship between the reactive kinetic parameter and the volatile matter are fond out, when the heating rate is 100C/min. The experiment results illustrate that the more the volatile matter is, the less the activation energy (E) and the Pre Exponential factor (A) are, and the difficulty rank of coal samples of spontaneous combustion is Jinggezhuang9#, Jinggezhuang11#, Tangshan, Qianjiaying, Tunlan.

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Mansha, M., A. R. Saleemi, and Badar M. Ghauri. "Kinetic models of natural gas combustion in an internal combustion engine." Journal of Natural Gas Chemistry 19, no. 1 (January 2010): 6–14. http://dx.doi.org/10.1016/s1003-9953(09)60024-4.

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Thanatawee, Phattharanid, Wanwisa Rukthong, Sasithorn Sunphorka, Pornpote Piumsomboon, and Benjapon Chalermsinsuwan. "Effect of Biomass Compositions on Combustion Kinetic Parameters using Response Surface Methodology." International Journal of Chemical Reactor Engineering 14, no. 1 (February 1, 2016): 517–26. http://dx.doi.org/10.1515/ijcre-2015-0082.

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AbstractThe aim of this research is to find the correlation between chemical compositions of biomass, including cellulose, hemicelluloses and lignin, and kinetic rates of biomass combustion. The combustion behavior of biomass constituent was studied by thermogravimetric analyzer. The correlations were generated by means of using Response Surface Methodology based on Simplex-Lattice experimental design. The results obtained from statistical analysis can be used to generate mathematical models and also contour plots which exhibited the relationship between biomass composition and its combustion kinetic. From the observation, the models and contour plots indicated the complexity of combustion mechanism. The correlations proposed by this research were expected to be potentially used to predict combustion behavior in case of real biomass.

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Journal articles on the topic 'Kinetic of combustion'

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