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All accepted papers of ICEEEE2018 has been recorded in Web of Science.

Keynote

If you are interested in being an invited speaker and share your ideas in the field of energy technology and power engineering, you are welcome to contact us for any inquiry: cfp@iceeee.org and send us with your CV, speech title and abstract.

Professor Dong Han
Shanghai Jiaotong University, China

Speech Title: Second-law Thermodynamic Analysis of Hydrogen Flames based on Thermochemistry and Chemical Kinetics
Abstract: Combustion is a highly irreversible process and is the primary source for exergy destruction in combustion engines. Previous studies pointed out that in combustion engines, 20% - 30% of the fuel chemical exergy would be lost as a result of combustion. However, the exergy loss regime in combustion has not been clearly elucidated. In this report, the exergy losses from flame propagation are attributed to entropy generation by heat conduction, mass diffusion and chemical reactions, as well as incomplete combustion. The contribution rates of different sources to the total exergy loss in hydrogen flames will be analyzed in detail. Further, the effects of fuel blending and charge dilution on the exergy loss from each source will be discussed based on the thermochemical and chemical kinetic analysis.

Professor Jinhua Wang
Xi'an Jiaotong University, China
Speech Title: Effect of highly hydrogen enrichment on lean premixed turbulent flame and swirl flame stabilization

Abstract: Hydrogen is the most promising clean fuel for engine and power generation. Hydrogen enriched hydrocarbons have emerged as a foremost candidate of the future low carbon energy system. Especially for the lean premixed combustion system, such a scheme will be potential for high efficiency and low pollutant emissions. Despite of the previous studies, the hydrogen enriched turbulent premixed flames and more realistic flames such as swirl flames need further investigation. The detailed flame structure, the flame characteristics under straining, and the flame-flow interactions have not been well understood. In this talk, effect of highly hydrogen enrichment on lean premixed turbulent flame and swirl flame stabilization was presented. Experiments have been conducted on various burners and wide range of conditions in Clean Combustion Center of Xi’an Jiaotong University. Multi-species measurement of OH-PLIF, CH2O-PLIF has been adopted. Multi-filed simultaneous measurement of PIV and OH-PLIF has been performed. The experimental results will help to better understand the hydrogen enriched flames.
One important impact of hydrogen addition is the enhancement on local molecular transport due to the high mass diffusion rate (about three times than methane). This leads to the common known preferential diffusion effects. Due to such effects, we observe the appearance of prevalent cusps on the flame front pointing to the burned region. The positively curved bulges convex to the unburned region also propagate upstream. Then the flame front is no longer smooth which we refer to as a kind of self-turbulence. This largely increases the turbulent burning velocity. Moreover, the external turbulence is found to promote the flame front wrinkling by distorting these positively curved bulges. Effects of hydrogen on the detail flame structure were investigated. The reaction zone and preheat zone were measured with synchronous OH and CH2O-PLIF. The hydrogen is observed to decrease the preheat zone thickness. The reaction zone is not obviously broadened within the “thin reaction zone”. However, the hydrogen is found to increase the thickness of the reaction zone slightly.
Hydrogen improves the flame stability, especially the blow-off of the high speed swirl flame in gas turbine combustor. The hydrogen addition was observed to increase the laminar flame speed and the adiabatic temperature. The hydrogen enriched hydrocarbons always tend to possess a negative Markstein number. This indicates an increased burning velocity of lean hydrogen flames under the strain, compared to the decrease trend of some large molecular fuels. The increased burning intensity with hydrogen is found to decrease the recirculating mass into the central recirculation zone (CRZ), which increases the CRZ temperature. The high adiabatic temperature also contributes to this effects. This is very important as a basic advantage for the flame stabilization. Another vital feature is that the hydrogen enhances the flame root. Flamelet conditioned excess straining and shear layer vortexes strongly act on the flame attachment. However, the hydrogen (1) increases the resistance to extinction at the flame root and (2) mitigates the effects of vortexes on promoting the blow-off.

Professor Zunhua Zhang
Key Laboratory of High Performance Ship Technology, Wuhan University of Technology, China
Speech Title: Progress in the marine LNG engine with onboard hydrogen addition via reformed exhaust gas recirculation

Abstract: For marine engines fueled with liquefied natural gas (LNG), the technique of exhaust gas–fuel reforming, which is known as the reformed exhaust gas recirculation (REGR), can be employed to reduce the air pollutant emissions from them. Specifically, on-board hydrogen-rich gas mixtures (i.e., the reformate) can be generated through catalytic reforming of the exhaust gas–fuel mixtures, and then the reformate is recirculated into the engine cylinders. Thus fuel modification, high-efficiency combustion and exhaust gas aftertreatment can be realized simultaneously. The present report will present our research progress in the investigations of combustion characteristics and chemical kinetic mechanisms for blends of natural gas and the reformate, features of hydrogen generation from the exhaust gas–fuel reforming, the interaction among fluid flow, heat and mass transfer and catalytic reactions in the exhaust gas–fuel reformer, and the performance and emission characteristics of marine natural gas engines with REGR. The feasibility of the REGR technique has been validated via both the bench test and the numerical simulation. On this basis, the industrialization demonstration of the REGR technique will be conducted next. The present study can provide solid support for the application of the REGR technique to the control of air pollutant emissions from marine engines fueled with LNG.






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