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《International Journal of Hydrogen Energy》2019,44(11):5538-5542
The research of hydrogen fuel internal combustion engine (HICE) had great significance facing the challenges of energy and environmental problems. Based on the detailed hydrogen-air reaction mechanism, the pre-mix model of CHEMKIN-Pro software was selected to simplify the detailed mechanism GRI-3.0. The most important elements and reactions was chose to construct framework mechanism firstly based on the sensitivity coefficient for H2O and NO formation, and additional elements and reactions were added to framework mechanism for complementing the oxidation path of N2 and H2. A simplified mechanism including 24-step elementary reaction was obtained and the laminar burning velocity calculated by this simplified mechanism matches well with the detailed mechanism in a wide range. This simplified mechanism was also applied in a CFD model which predicted the cylinder instantaneous pressure and NOx emission accurately within a large range of fuel air equivalent ratio. Showing that this mechanism has good applicability. 相似文献
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Hrvoje Mikulčić Jakov Baleta Xuebin Wang Jin Wang Fengsheng Qi Fan Wang 《International Journal of Hydrogen Energy》2021,46(45):23548-23563
Ammonia appears to be a potential alternative fuel that can be used as a hydrogen vector and fuel for gas turbines and internal combustion engines. Chemical mechanisms of ammonia combustion are important for the development of ammonia combustion systems, but also as a mean of investigation of harmful NOx emissions, so they can be minimized. Despite of large body of experimental and modelling work on the topic of ammonia combustion, there is still need for additional investigation of combustion kinetics.The object of this work is further numerical study of ammonia combustion chemistry under conditions resembling industrial ones. After literature review, three mechanisms of ammonia combustion that also include carbon chemistry are used for simulation of experimental premixed swirl burner with the aim of evaluating their performance. San Diego mechanism, that was also the most detailed one, proved to be the best in terms of emissions, but neither one of the models was able to accurately reproduce CO emission after equivalence ratio went beyond 0.81. It was also observed that oxygen is excessively consumed. This study contributes to the current knowledge by providing new insights in ammonia burning conditions closely resembling those in industrial applications, and consequently is expected that insights obtained will help in the design of real industrial burning systems. 相似文献
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某F级燃气电厂运行中发现NOx数值存在较大波动,通过分析和排查,发现烟气分析仪存在老化现象,同时CEMS仪表间存在布置不合理情况,通过处理NOx数值波动得以有效改善,可为同类电厂烟气系统数据异常处理提供参考。 相似文献
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以某F级燃机联合循环机组为例,考虑电价气价和年利用小时数等因素,研究燃机控制直接降NOx和使用SCR脱硝对于经济性的影响。 相似文献
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Antonella Ingenito 《International Journal of Hydrogen Energy》2018,43(50):22694-22704
The promising opportunity to reach intercontinental long distances in a few hours is a remarkable issue for both private companies and public organizations: teams of scientists, technicians and researchers in Europe, USA, China, Russia and India are working at national and international programs on long range high speed civil transport. The Space X's CEO also announced, at the IAC 2017 conference, the growing interest in developing a 30-min transatlantic passenger flight by means of a 2-stage rocket-based vehicle. Meeting the dwell requirement of antipodal ranges and high speeds is realistic through a new era of hydrogen-fuelled hypersonic airbreathing vehicles. The interest in hydrogen as aviation fuel has recently increased not only due to the growth of worldwide air travel and time reduction requirements, also for the dramatic rise of common aviation fuel prices, and the continuously increasing restrictive environmental issues.In the light of these changes that have occurred in fuel prices, emissions reduction imperatives and the currently higher demand for supersonic airline travels, hydrogen-fuelled hypersonic airbreathing airliners are a valuable chance with respect to other means of transport (i.e., a rocked based passenger transport). In fact, hydrogen is one of the most environmental friendly fuels, since no particulate and carbon oxide emissions are produced. Past objections on hydrogen as fuel for civil transport, such as safety, liquefying and storing hydrogen are now overcame and its technological maturity opens a large worldwide market for hydrogen as “green” fuel. However, since the opportunity for hydrogen as fuel for future fleets of airline transport resides in its “green” peculiarity, the investigation of the impact of the H2/air hot exhausts on the ozone layer depletion is mandatory. In fact, a lot of hypersonic cruise vehicles fly at an altitude of 25000–30000 m that corresponds to the ozonosphere. In this region, the concentration of ozone is maximum and NOx emissions may catalyse the ozone destruction.In this context, the goal of this paper is to estimate the effect of the H2/air emissions (i.e., nitrogen oxides, hydroxide and water vapor) of a fleet of 200 hydrogen fuelled hypersonic airliners flying once a day for 360 days from Brussels to Sydney, on the ozone layer and on the global temperature increase. 相似文献
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我国酸雨状况及综合防治对策研究 总被引:4,自引:0,他引:4
本文详细论述了酸雨及其形成机理、危害和我国酸雨状况,指出了我国防治酸雨的必要性,提出了酸雨综合防治的策略。结合北京市的特点,探讨了北京市酸雨防治的对策。 相似文献
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