共查询到19条相似文献,搜索用时 109 毫秒
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EGR和催化转化净化汽油车排气的试验研究 总被引:1,自引:0,他引:1
在发动机排气再循环和催化转化机理与车用汽油机排气特性研究的基础上,本文通过对车用汽油机装上EGR的催化转化装置后,在发动机台架上进行中低转速下的发动机负荷特性试验,探讨在有无EGR时对催化转化净化效果的影响。 相似文献
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基于乙醇汽油及EGR对汽油机排放的机理影响,本文通过不同EGR率及不同乙醇汽油配比,来研究对汽油机THC、C0、NOx、颗粒物的影响。 相似文献
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柴油机的EGR脉谱和柴油机排放曲线都是严重的非线性,模型过于复杂,不能直接用于控制.本文将人工神经网络应用于增压柴油机EGR控制上,建立了柴油机的BP网络模型,通过实验数据进行模拟分析,可以证明,人工神经网络辨识各参数间的关系简单易行,当学习样本足够多时,网络的预测值能够和试验值高度吻合. 相似文献
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一.技术创新方面
1.传统车用发动机技术升级从欧Ⅲ到欧Ⅵ的技术跨越。需要重点突破一批关键技术:汽油机——涡轮增压技术、可变气门正时技术、缸内直喷技术等;柴油机——先进燃油喷射系统、可变截面涡轮增压、EGR、SCR及DPF等后处理技术、电控技术等。 相似文献
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近几年来,韶关内燃机厂根据国内外市场的需要和发展规划,引进、消化、吸收国外先进技术,开发了76系列车用汽油机。通过几年努力,于1988年开发研制成功376Q型汽油机(见图23)并通过省级鉴定。89年根据市场和用户的要求又开发出376Q-1型汽油机,其主要技术规格见表5。92年工厂已基本建成年产7000台汽油机的生产能力,开始批量生产汽油机投放市场,深受用户欢迎。 相似文献
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针对柴油机废气再循环(Exhaust gas recirculation, EGR)系统传统开发流程中的计算机辅助工程(Computer aided engineering, CAE)技术应用的有效性、系统性和完整性等问题,以提升企业产品开发能力为目的,对CAE技术在柴油机EGR系统开发过程中的应用进行研究,在重新定义发动机CAE技术内容的基础上,以“整机-子系统-零部件”为开发模式,建立基于CAE技术的EGR系统开发流程。研究结果表明,仿真优化计算确定的EGR系统方案切实可行,在不明显影响柴油机动力性、经济性的情况下,NOx排放降低了20%左右,满足了EGR系统的开发目标;应用基于CAE技术的柴油机EGR系统开发流程,能够缩短开发周期,降低开发成本,提高开发质量,实现EGR系统开发过程的系统性、整体性和完整性,为EGR系统的有效开发提供一种新方法。 相似文献
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Jinyoung Cha Junhong Kwon Youngjin Cho Simsoo Park 《Journal of Mechanical Science and Technology》2001,15(10):1442-1450
The EGR system has been widely used to reduce nitrogen oxides (NOx) emission, to improve fuel economy and suppress knock by using the characteristics of charge dilution. However, as the EGR rate at a given engine operating condition increases, the combustion instability increases. The combustion instability increases cyclic variations resulting in the deterioration of engine performance and emissions. Therefore, the optimum EGR rate should be carefully determined in order to obtain the better engine performance and emissions. An experimental study has been performed to investigate the effects of EGR on combustion stability, engine performance, NOx and the other exhaust emissions from 1. 5 liter gasoline engine. Operating conditions are selected from the test result of the high speed and high acceleration region of SFTP mode which generates more NOx and needs higher engine speed compared to FTP-75 (Federal Test Procedure) mode. Engine power, fuel consumption and exhaust emissions are measured with various EGR rate. Combustion stability is analyzed by examining the variation of indicated mean effective pressure (COVimep) and the timings of maximum pressure (Pmax) location using pressure sensor. Engine performance is analyzed by investigating engine power and maximum cylinder pressure and brake specific fuel consumption (BSFC). 相似文献
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CAI Ruibin CHEN Zijian College of Automobile Engineering South China University of Technology Guangzhou China Guangdong Key laboratory for Electric Vehicle Research Guangzhou China 《机械工程学报(英文版)》2006,19(3):401-406
The working principle of a kind of compositive emission control system is inquired into, which includes exhaust heater, secondary air supplement, exhaust gas recirculation (EGR), thermal reactor and catalytic converter, etc. The purification effect of CO, HC and NOx emission of the gasoline spark ignite (S.I.) engine is studied. The entire vehicle driving cycle tests based on the national emission standard and a series of the gasoline engine-testing bench tests including full load characteristic experiment, load characteristic experiment and idle speed experiment are done. The results show that the system has a very good emission control effect to CO, HC and NOx of gasoline engine. The construction of the system is very simple and can be mounted on the exhaust pipe conveniently without any alteration of the vehicle-use gasoline engine. 相似文献
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为了降低柴油机NOx的排放量,设计了一种冷EGR温度控制器。该控制器可通过控制直流电动水泵的转速来调节冷却水的循环量,确保不同工况下的最佳EGR冷却温度。通过传感器信号获得EGR的冷却温度,如果EGR的冷却温度不在最佳冷却温度范围内,控制器通过PID控制改变脉宽调制信号PWM的占空比来调整水泵电机的平均电压以改变水泵的转速进而调节冷却水的循环量,从而实现冷EGR温度的自动控制。在CA498型柴油机上对该温度控制器进行了试验,结果表明,与未冷却的EGR系统相比,该冷EGR温度控制器可以有效地降低NOx的排放量。 相似文献
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胡明江 《振动、测试与诊断》2013,33(1):122-126
基于PCL-818HG型总线数据采集卡和S3C2410型高性能低功耗微处理器,开发了一种便携式柴油机废气再循环(exhaust gas recycle,简称EGR)瞬态参数的采集与诊断系统.运用DASYLab和Linux软件编写接口、标定与诊断程序,实现了对柴油机EGR系统的位移、压力、温度和转速等信号实时采集、处理与诊断等功能.依据柴油机瞬态测试循环法进行增压柴油机废气再循环系统的EGR阀自诊断、EGR率过大诊断和瞬态响应特性等试验.结果表明,该系统性能可靠、处理能力强、诊断精度高,能满足增压柴油机EGR性能瞬态参数的采集与诊断要求. 相似文献
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针对国内通用小型汽油机生产中出现的问题,为提高汽油机进排气系统的流通能力和降低整机排放,设计了用于通用小型汽油机进排气系统的稳流试验台,对稳流试验台用于汽油机的研究、零部件检验和整机质量控制的功能做了介绍,以1P68F汽油机为例,对汽油机的进排气系统进行了初步稳流试验,对试验结果进行了分析,结果表明通用小型汽油机进排气系统零部件流动性能普遍较差。按内燃机流动特性进行优化设计、处理好压铸件工艺要求与流通性能的矛盾,改进通用小型汽油机进排气系统零部件质量,能提高我国通用小型汽油机的性能和产品技术水平。 相似文献
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Diesel emission regulations have recently become more severe. An important goal in diesel engine research is the development of methods to reduce the emissions of NOx and PM (particulate matter). Cooled EGR (exhaust gas recirculation) system has been widely used to reduce the NOx and PM emissions of light-duty diesel engines. In this study, numerical analyses, rig tests and engine tests were performed to assess how changes in internal shape characteristics can improve the heat exchange efficiencies of EGR coolers. The heat exchange efficiencies of EGR coolers have been numerically and experimentally measured during a fouling process. The results show that the second type of oval EGR cooler tested (oval #2) exhibited better heat exchange efficiency than either the first type of oval EGR cooler was tested (oval #1) or the shell and tube cooler examined. The turbulence generated in exhaust gas flows by the wavy-finned design of the oval EGR coolers facilitated PM desorption that allows these coolers to self-purify. With respect to the two similar oval EGR coolers, the cooler with fin pitch 4 mm has better efficiency than the cooler with fin pitch 6 mm due to differences in the heat transfer areas of these coolers. Both CFD analyses involving extreme conditions of engine operation and engine fouling tests involving conditions experienced during vehicular operation indicate that the two oval coolers differed by less than 4% with respect to both initial heat transfer efficiency and heat transfer efficiency after a 78-hour fouling test. 相似文献
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文丘里管废气再循环系统对涡轮增压柴油机性能影响的研究 总被引:1,自引:0,他引:1
加装文丘里管的高压废气再循环(Exhaust gas re-circulation,EGR)进气系统,在兼顾柴油机经济性、动力性的前提下,研究该进气系统对NO_x排放的影响。根据一款柴油机的基本结构建立柴油机一维仿真计算模型和燃烧室的三维仿真计算模型。在对模型进行标定和对柴油机原机性能仿真计算的基础上,为进气系统引入文丘里管装置并对其结构参数进行优化设计。应用所建立的一维和三维柴油机模型,对文丘里管EGR系统柴油机的经济性、NO_x和Soot排放特性进行仿真计算研究,并对计算结果进行试验验证。研究结果表明,优化设计的文丘里管EGR系统可使柴油机在欧洲稳态循环(European steady state cycle,ESC)各工况下实现较为理想的EGR率,并在不明显影响柴油机燃油经济性的前提下,使NO_x排放量下降了约28.4%。文丘里管进气系统可以实现较为理想的高压EGR循环,在柴油机ESC工况下(怠速除外)能够达到较为理想的EGR率。 相似文献
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发动机可变气门正时技术(VVT,Variable Valve Timing)至今已经有30余年的历史,由于其省油、功升比大等优点,近年来得到了广泛的运用。针对在汽油发动机台架试验运行过程中,某汽油机VVT工作异常进行阐述,对该故障进行分析。通过对VVT系统的优化设计及相关的试验验证,从而有效地解决了故障问题。 相似文献