INVESTIGATION IN REDUCING EXHAUST EMISSIONS FROM TWO STROKE MOTORCYCLES

Test results of reducing two stroke motorcycle emissions with new type carburettors and electronic fuel injection systems are presented. Analyses and comparison between different systems are discussed. The adoption of electronically controlled injection and corresponding electronic control technique is an effective measure of prolonged vitality to improve emissions from two stroke motorcycles. Suggestions about the strategic steps of China′s motorcycle emission control are proposed.

Emission Performance of Motorcycles in Real-Road Conditions

WMTC,which means a worldwide motorcycle testing cycle,is now regarded as the most possible choice for the global motorcycle emission testing cycle,but whether or not it can be used in China is still unknown.In this study,a large number of data on the speed-time trace of motorcycles were sampled from various kinds of roads in 5 cities in China.Based on a series of criterion numbers defined,the driving character of motorcycles in the real-road conditions of China was obtained.With the aid of a specially designed program,an emission testing cycle that can indicate the driving characteristics of motorcycle in the real-road conditions was synthesized,and the exhaust emission tests of 20 motorcycles under the synchronized cycle and WMTC were carried out based on a CVS system and a motorcycle chassis dynamometer.The results show that although there do exist differences in some criterion numbers between the real-road condition and WMTC,such as proportion of idling mode,mean speed,mean running speed and the average acceleration and deceleration rates,the driving behaviors are similar.The results of exhaust emission tests indicate that the emission values of motorcycles under the synchronized cycle and WMTC have a relatively strong correlation.This means that WMTC can be introduced as a standard motorcycle emission test regulation into China.

Driving Cycle for Motorcycle Using Micro-Simulation Model

Driving cycle of vehicle has been used in emission estimation and fuel consumption study. Existing method of data collection using car chasing technique is expensive. The technique using micro simulation approach is cheaper and fast to derive the driving cycle. In this paper a traffic simulation model Driving Cycle Micro-Simulation Model for Motorcycle has been developed. The issue of lateral and longitudinal movement aspect in motorcycle driving has been examined in the model. Parameters to cover such movement have been built in the model and applied on a stretch in Edinburgh city of Scotland. Results from model have been both calibrated and validated. The results show that Driving Cycle Micro-Simulation Model for Motorcycle gives better representation of driving cycle and it can be used to understand the effect of driving modes on emission for better understanding of vehicular emission control.

Emissions and noise mitigation through use of electric motorcycles

Gasoline-powered motorcycles contribute disproportionately to traffic noise and emissions,so motorcycle electrification merits investigation.Recent advances in battery efficiency allow electric motorcycles(EMCs)to join electric cars and bicycles as a viable consumer option.This study quantifies noise and emissions using both simulations and experimental data,examines the factors that make motorcycles big offender and uses popular EMC makes and models to estimate the costs and benefits of electrification in the USA.Motorcycles produce more CO,CH4,NOx,HC and particulate matter per vehicle-mile travelled than passenger vehicles.Due to limited regulation of motorcycles and weak enforcement,the perceived noise level of motorcycles exceeds that of most other vehicles,being roughly double those of automobiles at speeds of over 30 mph and surpassing even those of medium trucks and buses at speeds of over 50 mph,at which point motorcycles exceeds the 80 dBA US standard limit.Electrification can resolve such issues,although range limitations and high prices are presently a barrier to widespread adoption.In order to realize these environmental benefits,it is important that electrification occurs with a corresponding shift away from coal as an energy source.Stricter emission regulations and stronger enforcement of existing prohibitions on certain forms of customization could also reduce the outlier status of gasoline-powered motorcycles.

Evaluating the emission status of light-duty gasoline vehicles and motorcycles in Macao with real-world remote sensing measurement

Roadside remote sensing measurement was used to explore the real-world emission status of light duty gasoline vehicles （LDGVs） and motorcycles in Macao. Both fuel-based and distance-based emission factors were derived using the mass balance method. The emission concentration profile of LDGVs illustrated the benefits of tightening emission standards at the source country or region of import. The distance-based emission factors for CO, HC and NOx of LDGVs registered before 2000 were 8.00, 1.04 and 1.36 g/km, respectively. The distance-based emission factors for CO, HC and NOx of LDGVs registered in or after 2000 were 1.16, 0.15 and 0.18 g/km, respectively. The fuel-based CO emission factors of light duty motorcycles （LDMCs） and heavy duty motorcycles （HDMCs） registered before 2000 were about 10 times higher than those of LDGVs of the same age group. As the emissions of LDGVs decreased more quickly after 2000, the gap widens for newer vehicles. The distance-based HC emission factors of LDMCs and HDMCs registered before 2000 were 4.81 and 2.91 g/km, respectively. The distance-based HC emission factors of LDMCs and HDMCs registered in or after 2000 were 3.52 and 0.93 g/km, respectively. The poor emission performance of motorcycles and their larger share in the traffic flow will cause them to be the major contributor to traffic CO and HC emissions. LDMCs, especially two-stroke models, should be the priority for vehicle emission control efforts in Macao.

基于双怠速法的摩托车排放检测及数据传输方案研究

随着车辆增加,摩托车尾气对城市大气污染影响日益突出。然而,摩托车定期排放检测没有联网,数据易变造,检测质量无法保证。而且,国产和进口摩托车种类多样,转速测量仪和密封接管适用度存在问题。本文提出了基于双怠速法的数据传输的关键技术方案。该技术方案包含了摩托车排放检测流程、分体式排气密封管以及数据传输的全套流程。目前,该技术方案已上海市建设了检测示范线,并实现了数据自动传输和示范应用。该技术为其他城市机动车污染防治提供经验,对排放监管和环境质量提升具有重要支持和借鉴意义。

液化石油气摩托车性能与排放

介绍了在国内率先开发成功的液化石油气 (LPG)摩托车的性能。对液化石油气摩托车进行了转鼓试验、道路噪声试验和百公里燃料消耗率的测试。结果表明 :新开发的液化石油气摩托车十五工况的整车排放明显优于欧Ⅰ限值 ,并且HC、NOx 排放优于欧Ⅱ限值 ,CO排放也与欧Ⅱ限值接近 ;液化石油气摩托车整车噪声低 ,达到我国 2 0 0 5年摩托车噪声限值的要求。

国产摩托车排放现状及控制进程分析

本文根据百余种国产摩托车排气污染物底盘测功机工况法测试结果,建立了相应的数据库。本文综述了国产摩托车排气污染物排放现状。在对欧洲和台湾摩托车排放控制进行考察和分析的基础上,结合我国情况,提出了摩托车排放控制进程建议。

汽油/液化石油气两用燃料摩托车的性能与排放研究

介绍了在国内率先开发成功的汽油/液化石油气(LPG)两用燃料摩托车的结构与性能。对该摩托车进行了转鼓试验、道路噪声试验和百公里燃料消耗率的测试。其结果表明:新开发的两用燃料摩托车在燃用LPG燃料时,其动力性能与原车相当,燃料经济性比燃用汽油时有所改善;其十五工况的排放,燃用汽油时接近欧Ⅱ限值,燃用LPG时优于欧Ⅱ限值。摩托车整车噪声达到2005年以后国家对摩托车的噪声限值。

CeO_2-ZrO_2复合氧化物对金属蜂窝整体催化剂性能的影响

用浸渍法制备了不同比例的CeO2 ZrO2 复合氧化物 ,并用XRD ,H2 TPR和BET等研究了复合氧化物的晶相、还原性能及热稳定性 .结果表明 ,所制备的CeO2 ZrO2 复合氧化物形成了固溶体 ,Ce0 6Zr0 4O2 比Ce0 90 Zr0 10 O2 更容易被H2 还原 ;110 0℃老化后 ,晶胞参数无明显变化 ,比表面积仍有 11 8m2 /g .模拟二冲程摩托车尾气组成 ,对用贵金属Pt,Pd ,Rh与CeO2及CeO2 ZrO2 固溶体所制备的催化剂进行了活性评价 .结果显示 ,110 0℃老化后 ,催化剂仍具有很高的氧化活性 .在贫氧区 ,Pt Pd Rh/Ce0 6Zr0 4O2 Al2 O3 对碳氢化合物氧化的催化活性则有一定的优势 ,是一种具有较高热稳定性的催化剂 .

125摩托车发动机电控燃油喷射系统的开发研究

本文提出了一种基于 12 5摩托车发动机的电控系统方案。详细介绍了该电控系统的软硬件组成 ,以及针对摩托车的种种特殊情况所采取的措施及控制策略。并对原机和电控发动机的经济性 ,动力性以及排放性能进行了对比。

电控摩托车汽油机排放特性的试验研究

利用MicroEFI电喷系统开展了摩托车汽油机在怠速工况和常用部分负荷工况下的排放研究。结果表明采用隔次喷射技术、点火优化以及稀混合燃烧可使怠速工况HC排放下降68%左右、CO下降60%左右,在部分负荷工况下的HC排放下降30%～40%、CO下降20%～60%、NOx下降30%～50%。

JS125-12A摩托车二次空气喷射系统的仿真

为了提高二次空气喷射系统的补气效果,建立了摩托车发动机模型,应用内燃机性能分析软件AVLBOOST,对JS125-12A型摩托车发动机进行性能计算,并与试验值进行了对比分析.在此基础上,建立二次空气喷射系统模型,并对包括补气孔位置、补气管直径、补气角度以及补气阀簧片刚度等二次空气喷射系统的主要设计参数进行性能预测和优化.结果显示,二次空气喷射点与排气口的距离为30mm,补气管直径为8mm,补气角度选择30°～60°,簧片刚度在100～500N/m之间取值时,二次空气喷射系统与发动机有最佳匹配.

FAI燃油喷射技术应对摩托车国Ⅲ排放标准的研究

中国摩托车第三阶段排放标准是世界上最为严格的摩托车排放标准之一,要达到其排放耐久性要求,传统的化油器供油方式在燃烧性能控制方面遇到了前所未有的困难,而应用基于汽车共轨系统的燃油喷射技术在摩托车整车布置及成本等方面难以被市场接受。将燃油系统高度集成化的FAI燃油喷射技术,可使系统的成本和性能得到更好的平衡。将FAI闭环电喷系统应用于国内主力摩托车车型,通过试验探讨了稳态工况空燃比、加速工况控制以及三元催化转换器等对摩托车排放的影响特性,最后确定了最佳空燃比控制窗口、与基本控制表和温度修正参数相关的控制策略、以及催化器生产工艺等,结果使摩托车的工况排放及排放耐久性完全达到国Ⅲ排放标准。

佛山限摩对摩托车出行特征及减排的影响分析

基于佛山市禅桂新限摩区域31个路段的流量和速度采集及COPERTⅣ模型计算得出的佛山市本地摩托车在不同道路类型上的排放因子,采用"自下而上"的机动车源排放清单编制方法,计算得到分道路类型的摩托车源污染物排放清单,并分析了限摩前后摩托车出行特征,同时,采用情景分析法评估了佛山市限摩政策产生的减排效果。结果表明:限摩后,次干道与主干道摩托车出行比例下降最明显,分别达到17.6%、13.9%,支路最小,只有1.9%;主干道各污染物的分担率最高,平均达到50%,其次是次干道,达到25%左右;即便是限摩后,佛山市摩托车出行在各种出行中所占有的比例仍超过20%,远高于国内平均水平的10%,说明佛山市居民摩托车出行比例过高。限摩后各道路类型的各种污染物的平均削减比例可达37.2%,年度变化带来的该值为35.6%,即同年度变化对比,限摩效果较明显。

用于摩托车尾气净化催化剂的金属蜂窝载体

由金属薄片或丝网制成的蜂窝状载体是继陶瓷载体之后用于制备汽车尤其是摩托车尾气净化催化剂的又一新型载体。与陶瓷载体相比较 ,由金属载体制成的催化剂具有起燃温度低、净化效率高、处理能力大、排气背压小、抗振性强和催化剂寿命长等优点 。

WMTC排放测试循环行驶特征的研究

利用所建立的评价准则数体系,研究了WMTC测试循环的行驶特征及其与FTP、ECE等排放测试循环的差异。研究结果表明,与我国现行的ECEⅡ和即将实行的ECEⅢ测试循环相比,WMTC测试循环怠速比例和稳态工况比例低,瞬态工况比例高,因此对摩托车的排放控制提出了更为苛刻的要求。为满足WMTC测试循环的限值要求,摩托车在速度-加速度平面上各峰值处所对应的工况点,必须以排放最低作为发动机控制策略的目标函数。

电喷摩托车发动机的排放控制研究

为应对日益严格的排放法规,摩托车电喷技术的应用无疑是一项有效的技术措施。本文通过电喷摩托车整车的排放特性试验研究,总结出解决摩托车排气污染物的电喷技术解决方案和变工况控制策略。

燃油种类对汽车尾气净化催化剂性能的影响

分别对燃用普通汽油和10%乙醇/汽油(E10)混合燃料的CG125型摩托车进行了10000km路试,比较了不同种类燃油的排放特性,并采用X射线光电子能谱,扫描电镜和电子探针考察了催化剂的积炭物种与积炭分布.结果表明,安装催化转化器后,燃用这两种燃料的摩托车尾气排放均能达到欧盟第二阶段排放标准,但催化转化器对E10尾气的净化效果明显低于普通汽油.燃用这两种燃料的摩托车尾气净化催化剂表面均存在积炭,径向不同部位积炭量顺序为中心层>过渡层>边缘层.燃用普通汽油时,催化剂表面积炭的碳物种主要是CHx,而燃用E10时的碳物种是(CH)xO.这说明要合理地设计催化转化器才能使尾气均匀地径向分布,而且必须针对燃油种类匹配适宜的催化剂.

摩托车低排放净化装置的研究

本文根据汽车排气净化原理在发动机排气管路中设置了兼有二次空气供给、EGR、热反应净化和催化转化等多项功能的排气净化装置 ,试验结果表明 ,该装置能较大幅度降低CO、HC和NOX的排放。