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燃烧特性 3

生物质 3

内燃机 2

循环流化床 2

污染控制 2

燃烧性能 2

Al-Cr203体系 1

Al@AP/PVDF纳米复合材料 1

CO₂捕集 1

NO_x 1

中国 1

中空纤维 1

二氧化碳捕集 1

亚稳态分子间复合材料 1

促进传递膜 1

全尺寸 1

关键设备 1

内燃机技术 1

内燃机，燃料喷雾，喷雾控制，喷雾形态，喷油器 1

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Optimization of kinetic mechanism for hydrogen combustion based on machine learning

《化学科学与工程前沿（英文）》 2024年第18卷第11期 doi: 10.1007/s11705-024-2487-0

摘要： The reduced mechanism based on the minimized reaction network method can effectively solve the rigidity problem in the numerical calculation of turbulent internal combustion engine. The optimization of dynamic parameters of the reduced mechanism is the key to reproduce the experimental data. In this work, the experimental data of ignition delay times and laminar flame speeds were taken as the optimization objectives based on the machine-learning model constructed by radial basis function interpolation method, and pre-exponential factors and activation energies of H₂ combustion mechanism were optimized. Compared with the origin mechanism, the performance of the optimized mechanism was significantly improved. The error of ignition delay times and laminar flame speeds was reduced by 24.3% and 26.8%, respectively, with 25% decrease in total mean error. The optimized mechanism was used to predict the ignition delay times, laminar flame speeds and species concentrations of jet stirred reactor, and the predicted results were in good agreement with experimental results. In addition, the differences of the key reactions of the combustion mechanism under specific working conditions were studied by sensitivity analysis. Therefore, the machine-learning model is a tool with broad application prospects to optimize various combustion mechanisms in a wide range of operating conditions.

关键词： hydrogen combustion machine learning chemical kinetics mechanism optimization

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Numerical study of novel OME combustion mechanism and spray combustion at changed ambient environments

《能源前沿（英文）》 2024年第18卷第4期页码 483-505 doi: 10.1007/s11708-024-0926-8

摘要： For a climate-neutral future mobility, the so-called e-fuels can play an essential part. Especially, oxygenated e-fuels containing oxygen in their chemical formula have the additional potential to burn with significantly lower soot levels. In particular, polyoxymethylene dimethyl ethers or oxymethylene ethers (PODEs or OMEs) do not contain carbon-carbon bonds, prohibiting the production of soot precursors like acetylene (C₂H₂). These properties make OMEs a highly interesting candidate for future climate-neutral compression-ignition engines. However, to fully leverage their potential, the auto-ignition process, flame propagation, and mixing regimes of the combustion need to be understood. To achieve this, efficient oxidation mechanisms suitable for computational fluid dynamics (CFD) calculations must be developed and validated. The present work aims to highlight the improvements made by developing an adapted oxidation mechanism for OME_1–6 and introducing it into a validated spray combustion CFD model for OMEs. The simulations were conducted for single- and multi-injection patterns, changing ambient temperatures, and oxygen contents. The results were validated against high-pressure and high-temperature constant-pressure chamber experiments. OH*-chemiluminescence measurements accomplished the characterization of the auto-ignition process. Both experiments and simulations were conducted for two different injectors. Significant improvements concerning the prediction of the ignition delay time were accomplished while also retaining an excellent agreement for the flame lift-off length. The spatial zones of high-temperature reaction activity were also affected by the adaption of the reaction kinetics. They showed a greater tendency to form OH* radicals within the center of the spray in accordance with the experiments.

关键词： oxygenated fuels reaction kinetics oxidation mechanisms computational fluid dynamics (CFD) oxymethylene ethers (OME) e-fuels multi-injection spray-combustion

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Combustion characteristics and kinetics of bio-oil

Ruixia ZHANG, Zhaoping ZHONG, Yaji HUANG

《化学科学与工程前沿（英文）》 2009年第3卷第2期页码 119-124 doi: 10.1007/s11705-009-0068-x

摘要： The combustion characteristics of bio-oils derived from rice husk and corn were studied by thermogravimetry analysis. According to the thermogravimetry (TG), differential thermogravimetry (DTG) and differential thermal analysis (DTA) curves of bio-oils in air and nitrogen atmosphere, we analyzed the combustion characteristics of different kinds of bio-oils in different atmospheres and worked out the combustion kinetics parameters of the bio-oil, providing reliable base data for the burning of bio-oil. The thermogravimetry indicated that the combustion process of bio-oil was divided into three stages. At the same time, the combustion process can be described by different order reaction models, and with the method of Coats-Redfern, the activation energy and frequency factor of different kinds of bio-oils were obtained.

关键词： bio-oil combustion characteristics combustion kinetics

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Numerical simulation of laminar premixed combustion in a porous burner

ZHAO Pinghui, CHEN Yiliang, LIU Minghou, DING Min, ZHANG Genxuan

《能源前沿（英文）》 2007年第1卷第2期页码 233-238 doi: 10.1007/s11708-007-0032-8

摘要： Premixed combustion in porous media differs substantially from combustion in free space. The interphase heat transfer between a gas mixture and a porous medium becomes dominant in the premixed combustion process. In this paper, the premixed combustion of CH

关键词： interphase mixture dominant Premixed combustion premixed combustion

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Entropy production analysis of swirling diffusion combustion processes

Deodat MAKHANLALL, Linhua LIU,

《能源前沿（英文）》 2010年第4卷第3期页码 326-332 doi: 10.1007/s11708-009-0058-1

摘要： A critical factor in the design of combustion systems for optimum fuel economy and emission performance lies in adequately predicting thermodynamic irreversibilities associated with transport and chemical processes. The objective of this study is to map these irreversibilities in terms of entropy production for methane combustion. The numerical solution of the combustion process is conducted with the help of a Fluent 6.1.22 computer code, and the volumetric entropy production rate due to chemical reaction, viscous dissipation, and mass and heat transfer are calculated as post-processed quantities with the computed data of the reaction rates, fluid velocity, temperature and radiative intensity. This paper shows that radiative heat transfer, which is an important source of entropy production, cannot be omitted for combustion systems. The study is extended by conducting a parametric investigation to include the effects of wall emissivity, optical thickness, swirl number, and Boltzmann number on entropy production. Global entropy production rates decrease with the increase in swirl velocity, wall emissivity and optical thickness. Introducing swirling air into the combustion system and operations with the appropriate Boltzmann number reduces the irreversibility affected regions and improves energy utilization efficiency.

关键词： entropy-based design radiation transfer swirl magnussen combustion-model

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Study on combustion characteristics of blended coals

LI Yonghua, WANG Chunbo, CHEN Hongwei

《能源前沿（英文）》 2007年第1卷第1期页码 96-100 doi: 10.1007/s11708-007-0010-1

摘要： Power plants in China have to burn blended coal instead of one specific coal for a variety of reasons. So it is of great necessity to investigate the combustion of blended coals. Using a test rig with a capacity of 640 MJ/h with an absolute milling system and flue gas online analysis system, characteristics such as burnout, slag, and pollution of some blended coals were investigated. The ratio of coke and slag as a method of distinguishing coal slagging characteristic was introduced. The results show that the blending of coal has some effect on NO but there is no obvious rule. SO emission can be reduced by blending low sulfur coal.

关键词： combustion capacity variety blended burnout

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Recent progress in electric-field assisted combustion: a brief review

《能源前沿（英文）》 2022年第16卷第6期页码 883-899 doi: 10.1007/s11708-021-0770-z

摘要： The control of combustion is a hot and classical topic. Among the combustion technologies, electric-field assisted combustion is an advanced techno-logy that enjoys major advantages such as fast response and low power consumption compared with thermal power. However, its fundamental principle and impacts on the flames are complicated due to the coupling between physics, chemistry, and electromagnetics. In the last two decades, tremendous efforts have been made to understand electric-field assisted combustion. New observations have been reported based on different combustion systems and improved diagnostics. The main impacts, including flame stabilization, emission reduction, and flame propagation, have been revealed by both simulative and experimental studies. These findings significantly facilitate the application of electric-field assisted combustion. This brief review is intended to provide a comprehensive overview of the recent progress of this combustion technology and further point out research opportunities worth investigation.

关键词： electric field combustion flame stabilization emission reduction flame propagation

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Catalytic combustion of volatile organic compounds using perovskite oxides catalysts—a review

《化学科学与工程前沿（英文）》 2023年第17卷第11期页码 1649-1676 doi: 10.1007/s11705-023-2324-x

摘要： With the rapid development of industry, volatile organic compounds (VOCs) are gaining attention as a class of pollutants that need to be eliminated due to their adverse effects on the environment and human health. Catalytic combustion is the most popular technology used for the removal of VOCs as it can be adapted to different organic emissions under mild conditions. This review first introduces the hazards of VOCs, their treatment technologies, and summarizes the treatment mechanism issues. Next, the characteristics and catalytic performance of perovskite oxides as catalysts for VOC removal are expounded, with a special focus on lattice distortions and surface defects caused by metal doping and surface modifications, and on the treatment of different VOCs. The challenges and the prospects regarding the design of perovskite oxides catalysts for the catalytic combustion of VOCs are also discussed. This review provides a reference base for improving the performance of perovskite catalysts to treat VOCs.

关键词： perovskite oxides volatile organic compounds catalytic combustion reaction mechanism

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Impact of oxygen enriched combustion on the performance of a single cylinder diesel engine

K. RAJKUMAR, P. GOVINDARAJAN

《能源前沿（英文）》 2011年第5卷第4期页码 398-403 doi: 10.1007/s11708-011-0157-7

摘要： In the present experiment, a computerized single cylinder diesel engine with a data acquisition system was used to study the effects of oxygen enriched combustion technology (OECT) on the performance characteristics. The use of different levels of oxygen-enriched air was compared with respect to percentage load. Increasing the oxygen content in the air leads to faster burn rates and increases the combustibility at the same stoichiometry (oxygen-to-fuel ratio). These effects have the potential to increase the thermal efficiency and specific power output of a diesel engine. The power increases considerably with oxygen enrichment. In addition, oxygen enrichment can also be considered as a way to reduce the sudden loss in power output when the engine operates in a high load condition. Assessed high combustion temperature from the oxygen enriched combustion leads to high combustion efficiency. OECT reduces the volume of flue gases and reduces the effects of greenhouse effects. Engine tests were conducted in the above said engine for different loads and the following performance characteristics like brake power (BP), specific fuel consumption (SFC), mean effective pressure, brake thermal efficiency, mechanical efficiency, and exhaust gas temperature were studied. The objective of this paper is to address, in a systematic way, the key technical issues associated with applying OECT to single cylinder diesel engines.

关键词： oxygen enriched combustion exhaust gas temperature brake power (BP) specific fuel consumption (SFC)

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Numerical simulation of charge stratifications to improve combustion and NO formation of lean-burn SI

Zhijun PENG ,

《能源前沿（英文）》 2009年第3卷第3期页码 353-358 doi: 10.1007/s11708-009-0035-8

摘要： The influences of charge stratification on spark ignition (SI) engine combustion and NO emission were analyzed using a phenomenological model. The mixture in the cylinder was divided spherically into three parts: a central core with a stoichiometric air-fuel charge, a dilution region without any combustible charge, and a mixing region lying between the core and the dilution region. Three mixture stratification parameters such as the extent of dilution in the mixing region, the extent of combustible charge in the mixing region, and the gradient of stratification in the mixing region were investigated. The results indicate that the extent of combustible charge in the mixing region could reduce in-cylinder NO formation significantly, compared with the extent of dilution in the mixing region. As long as the degree of dilution in the mixing region is within the dilution limit of the combustible charge, the gradient of dilution has little effect on combustion and NO formation.

关键词： charge stratification SI engine lean-burn combustion NO emission

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Effect of Fe on NO release during char combustion in air and O

Ying GU, Xiaowei LIU, Bo ZHAO, Minghou XU

《能源前沿（英文）》 2012年第6卷第2期页码 200-206 doi: 10.1007/s11708-012-0181-2

摘要： The chemistry of char was probed by studying nitrogen release under the reactions with air and oxy-fuel combustion. The experiments were conducted in a drop tube furnace and a fixed bed flow reactor. NO was observed during those experiments. The results show that the particle size of char generated at 1073 K in CO is larger than that in N . However, at 1573 K, it is smaller in CO atmosphere due to particle breaking by gasification of char and CO . The Fe addition increases the NO conversion ratio, and the effect of Fe rises steeply with the process going until it becomes stable in the end. The results also indicate that the release of NO increases more significantly with the Fe addition in oxy-fuel environment.

关键词： NO Fe char combustion CO₂

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Influence of temperature on cam-tappet lubrication in an internal combustion engine

CHANG Qiuying, YANG Peiran, WANG Jing, CHEN Quanshi

《机械工程前沿（英文）》 2007年第2卷第4期页码 489-492 doi: 10.1007/s11465-007-0085-8

摘要： The transient thermo-elastohydrodynamic (TEHL) lubrication simulation and isothermal elastohydrodynamic (EHL) simulation were performed on the exhausting cam-tappet friction pair of an internal combustion engine. Although by employing the two models the center pressure, the thickness of the lubricant film and friction coefficient obtained were similar in the changing trend during a rotating cycle, the parameters make a great difference, especially for the thickness of the lubricant film; the TEHL was four times thicker than the EHL. These results show that the temperature should not be neglected in the study of the lubrication of cam-tappet pairs.

关键词： coefficient combustion isothermal elastohydrodynamic temperature thickness

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Typical off-design analytical performances of internal combustion engine cogeneration

Xiaohong HE, Ruixian CAI

《能源前沿（英文）》 2009年第3卷第2期页码 184-192 doi: 10.1007/s11708-009-0007-z

摘要： Based on experimental data, typical off-design characteristic curves with corresponding formulas of internal combustion engine (ICE) are summarized and investigated. In combination with analytical solution of single-pressure heat recovery steam generator (HRSG) and influence of ambient pressure on combined heat and power (CHP) system, off-design operation regularities of ICE cogeneration are analyzed. The approach temperature difference Δ , relative steam production and superheated steam temperature decrease with the decrease in engine load. The total energy efficiency, equivalent exergy efficiency and economic exergy efficiency first increase and then decrease. Therefore, there exists an optimum value, corresponding to ICE best efficiency operating condition. It is worth emphasizing that Δ is likely to be negative in low load condition with high design steam parameter and low ICE design exhaust gas temperature. Compared with single shaft gas turbine cogeneration, Δ in ICE cogeneration is more likely to be negative. The main reason for this is that the gas turbine has an increased exhaust gas flow with the decrease in load; while ICE is on the contrary. Moreover, ICE power output and efficiency decrease with the decrease in ambient pressure. Hence, approach temperature difference, relative steam production and superheated steam temperature decrease rapidly while the cogeneration efficiencies decrease slightly. It is necessary to consider the influence of ambient conditions, especially the optimization of ICE performances at different places, on cogeneration performances.

关键词： internal combustion engine (ICE) cogeneration heat recovery steam generator (HRSG) off-design superheated steam saturated steam ambient pressure

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Progress in hydrogen enriched hydrocarbons combustion and engine applications

Zuohua HUANG, Jinhua WANG, Erjiang HU, Chenglong TANG, Yingjia ZHANG

《能源前沿（英文）》 2014年第8卷第1期页码 73-80 doi: 10.1007/s11708-013-0287-1

摘要： The paper summarized the work on hydrogen enriched hydrocarbons combustion and its application in engines. The progress and understanding on laminar burning velocity, flame instability, flame structure flame and chemical kinetics were presented. Based on fundamental combustion, both homogeneous spark-ignition engine and direct-injection spark-ignition engine fueled with natural gas-hydrogen blends were conducted and the technical route of natural gas-hydrogen combined with exhaust gas recirculation was proposed which experimentally demonstrated benefits on both thermal efficiency improvement and emissions reduction.

关键词： hydrogen enriched hydrocarbon combustion fundamental study engine application

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Dynamic modelling and simulation of a post-combustion CO capture process for coal-fired power plants

《化学科学与工程前沿（英文）》 2022年第16卷第2期页码 198-209 doi: 10.1007/s11705-021-2057-7

摘要： Solvent-based post-combustion capture technologies have great potential for CO₂ mitigation in traditional coal-fired power plants. Modelling and simulation provide a low-cost opportunity to evaluate performances and guide flexible operation. Composed by a series of partial differential equations, first-principle post-combustion capture models are computationally expensive, which limits their use in real time process simulation and control. In this study, we propose a first-principle approach to develop the basic structure of a reduced-order model and then the dominant factor is used to fit properties and simplify the chemical and physical process, based on which a universal and hybrid post-combustion capture model is established. Model output at steady state and trend at dynamic state are validated using experimental data obtained from the literature. Then, impacts of liquid-to-gas ratio, reboiler power, desorber pressure, tower height and their combination on the absorption and desorption effects are analyzed. Results indicate that tower height should be designed in conjunction with the flue gas flow, and the gas-liquid ratio can be optimized to reduce the reboiler power under a certain capture target.

关键词： CO₂ capture post-combustion capture simulation dominant factor