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学者姓名：纪常伟
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摘要 ：
As a promising power system, hydrogen-fueled Wankel rotary engine with excellent power and emission characteristic have received attention increasingly, which makes it of great interest to investigate it. To make up for blanks, this work was conducted to experimentally investigate the effect of spark plug position on the combustion and emission characteristic of hydrogen-fueled Wankel rotary engine under 1500 r/min, 66 kPa manifold absolute pressure and 1.5 excess air ratio. The results indicate that compared to the trailing spark plug, the leading spark plug is more suitable to hydrogen-fueled Wankel rotary engines, which can realize a wider ignition range, higher maximum brake torque, lower cyclic variation and better nitric oxide emission. The maximum brake torque of adopting trailing spark plug is 31.2 N.m, which is only 87% of the maximum brake torque of 36.0 N.m with adopting leading spark plug. At the maximum brake torque ignition timing, adopting leading trailing spark plug achieves lower cyclic variation and slightly higher thermal load than adopting trailing spark plug. Besides, the optimum central heat-release point of both spark plug positions locate between 35 and 40 degrees CA after the top dead center, and that of leading spark plug is later 2 degrees CA than that of trailing spark plug. Moreover, both spark plug positions obtained 0 nitric oxide emission at maximum brake torque ignition timing, which means that emission will not be a problem to limit the selection of spark plug position under tested conditions.
关键词 ：
Combustion Combustion Emission Emission Hydrogen Hydrogen Spark plug position Spark plug position Wankel rotary engine Wankel rotary engine
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| GB/T 7714 | Yang, Jinxin , Meng, Hao , Ji, Changwei et al. Comparatively investigating the leading and trailing spark plug on the hydrogen rotary engine [J]. | FUEL , 2022 , 308 . |
| MLA | Yang, Jinxin et al. "Comparatively investigating the leading and trailing spark plug on the hydrogen rotary engine" . | FUEL 308 (2022) . |
| APA | Yang, Jinxin , Meng, Hao , Ji, Changwei , Wang, Shuofeng . Comparatively investigating the leading and trailing spark plug on the hydrogen rotary engine . | FUEL , 2022 , 308 . |
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摘要 ：
为了探究进气角度对转子机性能的影响,以复合进气转子机为研究对象,构建并验证了适用于转子机工作过程的CFD模型。通过数值模拟的方法,对不同端面进气角度下氢气/汽油双燃料转子机的缸内流场和燃烧过程进行了研究。结果表明,随着进气角度的增加,从端面进气口进入的混合气与气缸后端盖的撞击点不断向燃烧室前方移动,从周边进气口进入的气体在燃烧室后端形成滚流,缸内混合气的平均涡度变大;在上止点附近缸内会形成与转子运动方向一致的单向流;在点火时刻缸内混合气的流速随着进气角度的增加略有降低,导致火焰传播速度变慢,燃料放热速率降低;相比于进气角度为0°时,当进气角度增加为60°时峰值缸压上升了7.44%,但NOx的生...
关键词 ：
氢气 氢气 端面进气角度 端面进气角度 转子机 转子机 燃烧过程 燃烧过程 缸内流场 缸内流场
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| GB/T 7714 | 马泽东 , 纪常伟 , 史程 et al. 端面进气角度对掺氢转子机性能的影响 [J]. | 广西大学学报(自然科学版) , 2021 , 46 (02) : 373-383 . |
| MLA | 马泽东 et al. "端面进气角度对掺氢转子机性能的影响" . | 广西大学学报(自然科学版) 46 . 02 (2021) : 373-383 . |
| APA | 马泽东 , 纪常伟 , 史程 , 杨金鑫 , 李欣 , 刘建峰 . 端面进气角度对掺氢转子机性能的影响 . | 广西大学学报(自然科学版) , 2021 , 46 (02) , 373-383 . |
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摘要 ：
本发明提供了一种识别电动汽车锂离子电池高温状况及快速精确灭火装置，包括一个灭火剂箱，箱体上表面有内嵌有一个灭火剂入口和出口阀，可以添加灭火剂或者更换不同的灭火剂，并保证电池包上盖的平整性。箱体下表面有单向阀，单向阀的出口处填装有的感温绝缘填料在感知到导热丝传递的最高温度后，如果达到热失控的临界温度就会熔化，进而释放出灭火剂箱内的灭火剂对即将热失控的电池单体进行精准的降温或灭火，减小了灭火剂箱的体积，并通过热绝缘电池隔板阻止该热失控电池单体蔓延至其它电池单体。单向阀与感温绝缘填料之间的感温线路将热失控信号传递至电动车内部的火灾报警器，提醒驾乘人员及时撤离，无需加装火灾报警器，降低了成本。
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| GB/T 7714 | 纪常伟 , 张知足 , 汪硕峰 et al. 一种识别电动汽车锂离子电池高温状况及精准灭火装置 : CN202110185698.9[P]. | 2021-02-11 . |
| MLA | 纪常伟 et al. "一种识别电动汽车锂离子电池高温状况及精准灭火装置" : CN202110185698.9. | 2021-02-11 . |
| APA | 纪常伟 , 张知足 , 汪硕峰 , 王兵 , 戚朋飞 , 张守芹 et al. 一种识别电动汽车锂离子电池高温状况及精准灭火装置 : CN202110185698.9. | 2021-02-11 . |
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摘要 ：
Hydrogen two-stage direct-injection enrichment is a novel injection strategy to utilize hydrogen more efficiently and effectively in gasoline rotary engines by inheriting the merits of hydrogen and direct injection simultaneously, such as flexible control, efficiency improvement, and emissions reduction. Based on the CONVERGE code with detailed chemistry solvers, a full-cycle CFD modeling including hydrogen jet-flow and combustion processes was presented and validated by experimental data. To understand the role of hydrogen two-stage injection in improving engine performance at part-load and lean-burn regime, six different injection arrangements for which two-stage injection strategies with variable hydrogen amount for each pulse (up to 30% for postinjection) had considered. The different effects on species evolution, combustion characteristics, knock propensity, and emissions formation were analyzed step-by-step. The simulation results showed that compared with direct-injected hydrogen for single-pulse, injecting adequate hydrogen in the second pulse after spark-ignition onwards performed a significant beneficial effect on the mixture stratification and flame propagation, especially for the trailing part of the rotor chamber, which contributed to the improvement in both combustion characteristics and thermal efficiency. The assessment of knock propensity demonstrated that the two-stage direct-injected hydrogen had the potential of mitigating the knock under lean operations. Using split injection accompanied by an optimized hydrogen allocation strategy allowed substantial unburned hydrocarbon and carbon monoxide reductions with a slight nitrogen oxide penalty rate due to the elevated combustion temperature.
关键词 ：
CFD modeling CFD modeling Hydrogen two-stage direct-injection Hydrogen two-stage direct-injection Knock propensity Knock propensity Rotary engine Rotary engine Stratified combustion Stratified combustion
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| GB/T 7714 | Shi, Cheng , Ji, Changwei , Ge, Yunshan et al. Parametric analysis of hydrogen two-stage direct-injection on combustion characteristics, knock propensity, and emissions formation in a rotary engine [J]. | FUEL , 2021 , 287 . |
| MLA | Shi, Cheng et al. "Parametric analysis of hydrogen two-stage direct-injection on combustion characteristics, knock propensity, and emissions formation in a rotary engine" . | FUEL 287 (2021) . |
| APA | Shi, Cheng , Ji, Changwei , Ge, Yunshan , Wang, Shuofeng , Wang, Huaiyu , Yang, Jinxin . Parametric analysis of hydrogen two-stage direct-injection on combustion characteristics, knock propensity, and emissions formation in a rotary engine . | FUEL , 2021 , 287 . |
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摘要 ：
Recently, ammonia is considered to be an energy medium for hydrogen or energy storage and ammonia/hydrogen can be a potential fuel blend for the spark-ignition engine. Nevertheless, the combustion properties of ammonia/hydrogen mixtures could be distinctive under different initial conditions. In this study, several essential combustion properties, including laminar burning velocity, minimum ignition energy, NOx and ammonia emissions, combustion efficiency, and mixture heating values of ammonia/hydrogen/air premixed combustion were extensively studied under a wide range of equivalence ratios (), hydrogen fractions (α) and different compression ratio using one-dimensional laminar planar flame and compared with stoichiometric methane, methanol, and ethanol combustion. The behavior of NOx generation changing with and α was analyzed in detail. Results showed that most properties of ammonia/hydrogen combustion could be comparable to that of hydrocarbon fuels under engine-relevant conditions, except for the mixture heating value is slightly lower in all conditions. Besides, the NO mole fraction non-monotonically changes with and α due to the competition between the effects caused by the reduction of nitrogen-atom species and the enrichment of H/O radicals. The NO mole fraction of stoichiometric ammonia/hydrogen could be even lower than that of hydrocarbons. Considering the properties of hydrocarbon fuels as a reference, promising working conditions for ammonia/hydrogen mixtures are from 1.0 to 1.05 and α from 40% to 60%. Besides, a high compression ratio is more suitable for ammonia/hydrogen mixtures due to the excellent knock resistance ability of NH3/H2 and better improvement than hydrocarbon fuels under high compression ratio. © 2020 Hydrogen Energy Publications LLC
关键词 ：
Ammonia Ammonia Engines Engines Hydrocarbons Hydrocarbons Hydrogen fuels Hydrogen fuels Hydrogen storage Hydrogen storage Ignition Ignition Mixtures Mixtures Nitrogen oxides Nitrogen oxides
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| GB/T 7714 | Wang, Du , Ji, Changwei , Wang, Shuofeng et al. Numerical study of the premixed ammonia-hydrogen combustion under engine-relevant conditions [J]. | International Journal of Hydrogen Energy , 2021 , 46 (2) : 2667-2683 . |
| MLA | Wang, Du et al. "Numerical study of the premixed ammonia-hydrogen combustion under engine-relevant conditions" . | International Journal of Hydrogen Energy 46 . 2 (2021) : 2667-2683 . |
| APA | Wang, Du , Ji, Changwei , Wang, Shuofeng , Yang, Jinxin , Wang, Zhe . Numerical study of the premixed ammonia-hydrogen combustion under engine-relevant conditions . | International Journal of Hydrogen Energy , 2021 , 46 (2) , 2667-2683 . |
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摘要 ：
Based on a retrofitted Wankel engine, fundamental experiments and numerical simulations were conducted to investigate the role of the hydrogen addition under stoichiometric and lean combustion conditions. The testbench recording of in-cylinder pressure, heat release, cycle-to-cycle fluctuation, and exhaust emissions were used to characterize fuel combustion. The verified CFD model clarified the inherent mechanisms behind experimental data. Results showed that the introduction of hydrogen addition caused combustion temperature to increase, the timing taken for active radical formations was significantly advanced, and the peak concentrations increased. This contributed to the increased pressure and the shortened combustion phasing in experiments. There was a proportional correspondence of the early flame growth and cyclic variation. Hydrogen addition has a minimal effect on the turbulent intensity after spark timing. However, adopting a highly diluted mixture caused the enhanced turbulent intensity, which was responsible for improving the stability of the engine. Due to the synergistic effects of the work delivery, cyclic fluctuation, and exhaust temperature, a larger hydrogen addition with stoichiometric operation showed lower higher brake thermal efficiency. Nitrogen oxide emissions increased with hydrogen enrichment and reduced with a higher degree of mixture dilution owing to a close positive correlation between the mass elevated-temperature and NOx formation. Benefits from sufficient oxygen concentration and elevated combustion temperature, the chain transfer process can be accelerated. This explained why CO emissions decreased at a larger hydrogen-enriched and leaner condition in the experimental investigation. Increasing the hydrogen content provided improvement in the desired HC emissions for all operating points.
关键词 ：
Combustion Combustion Emissions performance Emissions performance Excess air ratio Excess air ratio Hydrogen addition Hydrogen addition Wankel engine Wankel engine
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| GB/T 7714 | Shi, Cheng , Ji, Changwei , Wang, Shuofeng et al. Experimental and numerical study of combustion and emissions performance in a hydrogen-enriched Wankel engine at stoichiometric and lean operations [J]. | FUEL , 2021 , 291 . |
| MLA | Shi, Cheng et al. "Experimental and numerical study of combustion and emissions performance in a hydrogen-enriched Wankel engine at stoichiometric and lean operations" . | FUEL 291 (2021) . |
| APA | Shi, Cheng , Ji, Changwei , Wang, Shuofeng , Yang, Jinxin , Wang, Huaiyu . Experimental and numerical study of combustion and emissions performance in a hydrogen-enriched Wankel engine at stoichiometric and lean operations . | FUEL , 2021 , 291 . |
| 导入链接 | NoteExpress RIS BibTex |
摘要 ：
The application of hydrogen direct-injection enrichment improves the performance of gasoline Wankel rotary engine, and the hydrogen injection strategy has a significant impact on combustion, knock, and emissions. The Z160F Wankel rotary engine was used as the investigated compact engine, and the simulation model was developed using CONVERGE software. The combustion, knock and emissions characteristics of the engine were studied with the different mass flow of hydrogen injection, i.e., the trapezoid, wedge, slope, triangle and rectangle type of gas injection rate shape. In the numerical simulations, the in-cylinder pressure oscillations were monitored using monitoring points, and the knock index (KI) was used as an evaluation indicator. The study revealed that the gas injection rate shape significantly affected the mixture of hydrogen and air, thus impacting combustion, knock and emissions. When the injection rate shape was rectangle, the flame speed was faster, the peak pressure in the cylinder was higher, and the corresponding crank angle was earlier, which led to higher pressure oscillations in the cylinder and larger KI. Based on the rectangle injection rate shape, the KI decreased by 75.81%, 33.47%, 26.46% and 76.58% for trapezoid, wedge, slope, and triangle, respectively, and the indicated mean effective pressure increased by 15.68%, 5.07%, 0.56% and 14.98%, respectively. Due to the small difference in maximum temperature, which resulted in very little variation in nitrogen oxides for each injection rate shape, the total hydrocarbon emissions of the trapezoid and triangle injection rate shape was high due to the delayed combustion phase. This paper provides a solution for direct hydrogen injection to improve the combustion, knock and emissions behavior of the rotary engine. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
关键词 ：
Combustion Combustion Emissions Emissions Gas injection rate shape Gas injection rate shape Hydrogen direct-injection enrichment Hydrogen direct-injection enrichment Knock Knock Wankel rotary engine Wankel rotary engine
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| GB/T 7714 | Wang, Huaiyu , Ji, Changwei , Shi, Cheng et al. Investigation of the gas injection rate shape on combustion, knock and emissions behavior of a rotary engine with hydrogen direct-injection enrichment [J]. | INTERNATIONAL JOURNAL OF HYDROGEN ENERGY , 2021 , 46 (28) : 14790-14804 . |
| MLA | Wang, Huaiyu et al. "Investigation of the gas injection rate shape on combustion, knock and emissions behavior of a rotary engine with hydrogen direct-injection enrichment" . | INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 46 . 28 (2021) : 14790-14804 . |
| APA | Wang, Huaiyu , Ji, Changwei , Shi, Cheng , Wang, Shuofeng , Yang, Jinxin , Ge, Yunshan . Investigation of the gas injection rate shape on combustion, knock and emissions behavior of a rotary engine with hydrogen direct-injection enrichment . | INTERNATIONAL JOURNAL OF HYDROGEN ENERGY , 2021 , 46 (28) , 14790-14804 . |
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摘要 ：
This work aims to improve the idle performance of the n-butanol rotary engine by blending hydrogen and reducing idle speed. Hydrogen volume percentage (beta(H2)) changes from 0 to 7.94% and the idle speed decreases from 2600 to 2400 rpm. The test results show that the engine can achieve better stability and economy due to the coupling effect of mixing hydrogen and reducing the idling. The total fuel flow rate reduces from 24.57 MJ/h at 2600 rpm when pure n-butanol is fueled to 19.35 MJ/h at 2400 rpm when beta(H2) equals to 7.94%. The period of flame development and propagation are observably decreased by blending hydrogen even if reducing idle speed has a few negative effects. Hydrogen enrichment is an effective way to reduce the emissions of CO and HC. Besides, the negative effects of reducing idle speed on HC and CO emissions are decreased to a negligible level when beta(H2) passes about 7%. Besides, NOx emission is maintained at an extremely low value in the testing range. Also, enrichment hydrogen can compensate for the negative effects on combustion and emissions of reducing idle speed.
关键词 ：
Combustion Combustion Emissions Emissions Hydrogen enrichment Hydrogen enrichment Idle speed reduction Idle speed reduction N-butanol N-butanol Wankel rotary engine Wankel rotary engine
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| GB/T 7714 | Meng, Hao , Ji, Changwei , Wang, Shuofeng et al. Optimizing the idle performance of an n-butanol fueled Wankel rotary engine by hydrogen addition [J]. | FUEL , 2021 , 288 . |
| MLA | Meng, Hao et al. "Optimizing the idle performance of an n-butanol fueled Wankel rotary engine by hydrogen addition" . | FUEL 288 (2021) . |
| APA | Meng, Hao , Ji, Changwei , Wang, Shuofeng , Wang, Du , Yang, Jinxin . Optimizing the idle performance of an n-butanol fueled Wankel rotary engine by hydrogen addition . | FUEL , 2021 , 288 . |
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摘要 ：
To achieve more efficient and robust combustion, split direct-injected hydrogen as a new injection strategy for rotary engines was used to clarify the influences of various injection parameters, including hydrogen amount for each pulse, the dwell between pulses, and secondary injection pulse-width, on combustion performance and emissions formation by CFD modeling. The results of this investigation confirmed the benefit of split direct-injection as a useful means to govern mixture stratification which enabled the combustion more effective and rapid compared to single-injection mode. Enhanced combustion could be achieved by increasing the mass fraction of post-injection with an optimized dwell between injections. Further investigation on secondary injection pulse-width demonstrated that engine performance was substantially improved with a wider second injection pulse. From one side, as the secondary injection pulse-width was increased, the surrounding mixture distribution of the spark-plug location was richer, which was confirmed as a beneficial inhomogeneous circumstance of hydrogen to accelerate the burning rate. From another side, strong tumble level and turbulence intensity were of significant importance for facilitating the combustion process and getting optimal thermal efficiency. For emissions formation, split direct-injected hydrogen made a near-zero HC and CO emissions at the price of a comparable increase of NOx emissions. © 2020 Elsevier Ltd
关键词 ：
Combustion Combustion Direct injection Direct injection Hydrogen Hydrogen Internal combustion engines Internal combustion engines Mixtures Mixtures Rotary engines Rotary engines
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| GB/T 7714 | Shi, Cheng , Ji, Changwei , Ge, Yunshan et al. Effects of split direct-injected hydrogen strategies on combustion and emissions performance of a small-scale rotary engine [J]. | Energy , 2021 , 215 . |
| MLA | Shi, Cheng et al. "Effects of split direct-injected hydrogen strategies on combustion and emissions performance of a small-scale rotary engine" . | Energy 215 (2021) . |
| APA | Shi, Cheng , Ji, Changwei , Ge, Yunshan , Wang, Shuofeng , Yang, Jinxin , Wang, Huaiyu . Effects of split direct-injected hydrogen strategies on combustion and emissions performance of a small-scale rotary engine . | Energy , 2021 , 215 . |
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摘要 ：
To investigate the influence of operation parameters on the cyclic variation of the Wankel rotary engine with hydrogen enrichment, an intelligent regression model based on the support vector machine (SVM) was implemented to predict the cyclic variation. For modeling the prediction model, the cyclic variation of speed (CoVn) and cyclic variation of the main combustion duration (CoVCA10-90) were used as an evaluator for idle and part load conditions, respectively. The operation conditions including main fuel type (gasoline and n-butanol), hydrogen volume percentage (βH2), excess air ratio (λ), ignition timing (IT)and speed were used as independent variables. When optimizing the prediction model, the data processing method, kernel function, loss function and optimization method on the prediction performance were discussed in detail. The results indicated that an optimized model can be obtained by using genetic algorithm combined with [0, 1] data processing method, and the coefficient of determination, mean square error and mean absolute percentage error of CoVn were 0.9904, 0.0783 and 0.3845%, corresponding to CoVCA10-90 were 0.9972, 0.0197 and 1.1729%, respectively. For the CoVn, gasoline as the main fuel was lower than the n-butanol at the same operating condition. The CoVn at high speed was greater than that at low speed. When operating at part load conditions, the CoVCA10-90 decreased with the increasing βH2, and first decreased and then increased with advancing IT. © 2021 Elsevier Ltd
关键词 ：
Data handling Data handling Engines Engines Forecasting Forecasting Gasoline Gasoline Genetic algorithms Genetic algorithms Hydrogen Hydrogen Hydrogen fuels Hydrogen fuels Ignition Ignition Mean square error Mean square error Regression analysis Regression analysis Support vector machines Support vector machines
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| GB/T 7714 | Wang, Huaiyu , Ji, Changwei , Shi, Cheng et al. Development of cyclic variation prediction model of the gasoline and n-butanol rotary engines with hydrogen enrichment [J]. | Fuel , 2021 , 299 . |
| MLA | Wang, Huaiyu et al. "Development of cyclic variation prediction model of the gasoline and n-butanol rotary engines with hydrogen enrichment" . | Fuel 299 (2021) . |
| APA | Wang, Huaiyu , Ji, Changwei , Shi, Cheng , Ge, Yunshan , Wang, Shuofeng , Yang, Jinxin . Development of cyclic variation prediction model of the gasoline and n-butanol rotary engines with hydrogen enrichment . | Fuel , 2021 , 299 . |
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