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1.
《中国自行车》2014,(4):74-75
正由浙江省自行车电动车行业协会、浙江省自行车电动车商会主办,浙江华达展览有限公司和上海协升展览有限公司共同承办的"第35届中国浙江国际自行车电动车展览会"(以下简称"浙江展")定于2014年11月21日—23日在宁波国际会展中心隆重举行。  相似文献   

2.
给你的客户更换过燃油泵后,让其在整个使用寿命内能够正常工作的关键是保持燃油系统的清洁.本文将从专业维修的角度讲述如何才能够做到这一点.  相似文献   

3.
和三一充满活力的红不同,位于E2室内展馆的维特根用明亮的绿彰显它的环保主旨。随着人们的环保意识提高,在选择某种技术、材料或者某款设备时,环境友好型往往更受青睐,而同时契合循环经济、环境的可持续发展观念www.roadm-china.com  相似文献   

4.
最近几年,我从未感到站在F1专家的立场上会如此难以胜任。  相似文献   

5.
《汽车与配件》2013,(49):4-4
近期,多地连日的雾霾天气让老百姓切身体会到了环境污染的严重性。戴上口罩只是治标不治本的方法,要改善空气质量,还须多管齐下。推广新能源汽车就是对环保做出贡献的一种有效方式。  相似文献   

6.
郑刚 《摩托车》2011,(2):6-6
我们中国人的新年终于来了!展望新的一年,行走,还将是我生活的重要部分。为此,我给自己准备了两个新年礼物,一台尼桑电喷Y60四驱越野车,另一个则是KTM640ADV。后者也将是我今后一段时间里主要的自驾伙伴。  相似文献   

7.
存在的就是合理的   总被引:1,自引:0,他引:1  
  相似文献   

8.
本文在总结传统测试理论存在的问题的同时,给出软件测试的几个发展方向,如测试与开发相融合,探索性测试和自动化测试将被大量采用,软件在设计时应该考虑可测性等。  相似文献   

9.
10.
久陵 《汽车与配件》2009,(38):14-15
看起来这是一个出乎意料之外的美国政府决定。因为在此之前,基于双方政治经济关系发展良好,关于中国输美轮胎特保案的前景,中美业界均呈现了相当的乐观氛围。  相似文献   

11.
进气预混甲醇降低柴油机碳烟与NOx排放的影响参数研究   总被引:1,自引:0,他引:1  
姚春德  李云强  王银山  段峰  吉庆 《汽车工程》2004,26(6):635-638,685
在485QDI自然吸气直喷式柴油机上研究了不同喷嘴、不同供油定时、不同喷醇的起点对进气预混甲醇发动机的碳烟、NOx排放和经济性的影响。研究结果表明,为了降低碳烟和NOx排放以及提高燃油经济性,与燃用纯柴油的发动机相比,进气预混甲醇发动机的柴油喷射定时可以保持不变或稍小,但燃油喷嘴的孔径应适当减小,预混甲醇的发动机负荷起点应适中。  相似文献   

12.
《JSAE Review》1998,19(1):21-26
The effect of injection nozzle, diesel fuel density (volatility) and cetane number on diesel exhaust emissions were investigated. Decreasing injection nozzle hole diameter decreases PM emission. However, a small nozzle hole increases NOx emission and decreases the effect of fuel on PM emission. Decreasing fuel density is effective for reduction of NOx emission. But the effect is smaller than that of nozzle hole diameter and injection pressure. Furthermore injection timing retardation decreases the effect of fuel density on NOx emission.  相似文献   

13.
The purpose of this study is to understand the operational characteristics of a diesel engine that uses BD20 reformed by ultrasonic energy irradiation. In particular we study the effects of tuning injection delay and EGR rate. BD containing about 10% oxygen has attracted attention due to soaring crude oil prices and environmental pollution. This oxygen decreases soot by promoting combustion, but it also increases NOx. To solve this problem, injection timing may be delayed or an EGR system may be applied. These adjustments normally lower engine power and increase exhaust emission but, in using fuel reformed by ultrasonic energy irradiation (which is changed physically and chemically to promote combustion), we may hope to circumvent this problem. To control the duration of the ultrasonic energy irradiation, the capacity of the chamber in an ultrasonic energy fuel supply system was tested at 550cc and 1100cc capacities. As for the results of the experiment, we could identify the optimum EGR rate by investigating the engine performance and the characteristics of exhaust emissions according to the injection timing and the EGR rate while ultrasonically irradiated BD20 was fed to a commercial diesel engine. With UBD20 (at an injection timing of BTDC 16°), the optimum EGR rate, giving satisfactory engine performance and exhaust emissions characteristics, was in the range of 15∼20%.  相似文献   

14.
针对1130单缸柴油机研究了喷油嘴油线分布、喷油嘴孔数和喷油嘴针阀开启压力对分层燃烧甲醇发动机性能的影响。试验结果表明,燃油系统参数对分层燃烧甲醇发动机的性能有比较明显的影响。  相似文献   

15.
Increasing petroleum prices, increasing threat to the environment from exhaust emissions and global warming have generated intense international interest in developing renewable and alternative non-petroleum fuels for engines. Evolving feasible technology and recurring energy crisis necessitated a continued investigation into the search for sustainable and clean-burning renewable fuels. In this investigation, Honge oil methyl ester (HOME) was used in a four stroke, single cylinder diesel engine. Tests were carried out to study the effect of fuel injection timing, fuel injector opening pressure (IOP) and injector nozzle geometry on the performance and combustion of CI engine fuelled with HOME. Injection timing was varied from 19°bTDC (before top dead centre) to 27°bTDC in incremental steps of 4°bTDC; injector opening pressure was varied from 210 bar to 240 bar in steps of 10 bar. Nozzle injectors of 3, 4 and 5 holes, each of 0.2, 0.25 and 0.3 mm size were selected for the study. It was concluded that retarded injection timing of 19°bTDC, increased injector opening pressure of 230 bar and 4 hole nozzle injector of 0.2 mm size resulted in overall better engine performance with increased brake thermal efficiency (BTE) and reduced HC, CO, smoke emissions. Further air-fuel mixing was improved using swirl induced techniques which enhanced the engine performance as well.  相似文献   

16.
在自然吸气CA498发动机上,试验研究了匹配氧化型后处理器后,静态供油提前角对柴油机性能及排放指标的影响。试验结果表明,匹配后处理器,优化供油提前角后,自然吸气的CA498发动机排放可以达到欧Ⅲ水平;但由于提前角减小,排气背压增大,发动机燃油消耗率上升8%左右。  相似文献   

17.
改善火花助然甲醇发动机小负荷经济性的研究   总被引:4,自引:0,他引:4  
小负荷时经济性差,是火花助燃甲醇发动机存在的主要问题。以1130立式水冷直喷柴油单缸机为对象,研究了点火系统、压缩比、喷油嘴油线分布和喷油嘴针阀开启压力等因素对火花助燃甲醇发动机小负荷时经济性的影响,并将之与柴油发动机进行了对比分析。  相似文献   

18.
This paper presents an experimental study that involves an application of the Taguchi method and grey relational analysis to determine the optimum factor level to obtain optimum multiple-performance characteristics of a diesel engine run with different low-percentage thumba biodiesel-diesel blends. Four factors, namely, low-percentage thumba biodiesel-diesel blend, compression ratio, nozzle opening pressure and injection timing were each considered at three levels. An L9 orthogonal array was used to collect data for various engine performance- and emission-related responses under different engine loads. The signal-to-noise (S/N) ratio and grey relational analysis were used for data analysis. The results of the study revealed that the combination of a blend consisting of 30% thumba biodiesel (B30), a compression ratio of 14, a nozzle opening pressure of 250 bar and an injection timing of 20° produces maximum multiple performance of a diesel engine with minimum multiple emissions from the engine.  相似文献   

19.
Lean NOx trap (LNT) catalyst has been used to reduce NOx emissions from diesel engines. The LNT absorbs NOx in lean condition and discharges N2 by reducing NOx in rich conditions. Thus, it is necessary to make exhaust gas lean or rich conditions for controlling LNT system. For making a rich condition, a secondary injector was adopted to inject a diesel fuel into the exhaust pipe. In the case of secondary injector, the behavior of spray is easily affected by high temperature (i.e., 250 ~ 350 °C) occurred in the exhaust manifold. Therefore, it is needed to investigate the spray behavior of diesel fuel injected into an exhaust manifold, as well as the conversion characteristics for a lean NOx trap of a diesel engine with LNT catalyst. The characteristics of exhaust emissions in NEDC (New European Driving Cycle) mode were analyzed and spray behaviors were visualized in various exhaust gas conditions. The results show that as the exhaust gas mass flow increases, the spray cone angle becomes broad and the fuel is directed to the flow field. Besides, the cone angle of spray is decreased by centrifugal force caused in exhaust gas flow field. In addition, the effects of nozzle installation degree, injection quantity, and exhaust gas flow on NOx conversion performance were clarified.  相似文献   

20.
以某4缸增压直喷柴油机为样机,利用专业试验台架,在优化喷油提前角和EGR阀开度的前提下,联合利用氧化催化器(DOC)及微粒氧化催化转化器(POC)技术对柴油机尾气排放进行了试验研究,并总结了DOC和POC技术对柴油机排放的影响规律.试验结果表明,通过优化喷油提前角及EGR阀开度,并且选择正确的DOC与POC的布置形式,...  相似文献   

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