汽油/液化石油气两用燃料通用小型发动机排放性能试验分析

我们以一型号为192F型汽油/液化石油气两用燃料通用小型发动机为研究对象,介绍了该发动机的燃料供给系统结构,并根据此类发动机排放测试标准GB 26133-2010进行汽油和液化石油气2种燃料的排放性能试验。通过对试验结果的分析,该发动机燃用液化石油气比燃用汽油CO排放量降低,NOx排放增加。     

汽油—液化石油气（LPG）两用燃料发动机的研究

介绍了汽油－液化石油气（LPG）两用燃料发动机空燃比的调节和作者研制成功的无混合器式双蒸发器LPG供气系统,该供气系统取消了LPG发动机惯用的混合器,在原机双腔化油器的主、副腔喉管处钻孔,接入LPG主供气系和LPG加浓系,从而取消了混合器,解决了全负荷时动力性与部分负荷时燃料经济性、排放之间的矛盾,取得了良好的效果。用该系统改装的汽油－LPG两用燃料发动机,在燃用汽油时性能无任何变化,燃用LPG时取得了动力性、燃料经济性和排放指标俱佳的效果。     

甲醇和二甲醚燃料在发动机中的应用现状

论述了我国发展甲醇和二甲醚燃料的必要性,并分析了甲醇和二甲醚(DME)作为发动机燃料的优势和不利因素,详细阐述了目前汽油机、柴油机和HCCI发动机燃用甲醇和二甲醚燃料的现状,指出了今后发动机代用燃料的发展方向。     

汽油/液化石油气(LPG)两用燃料发动机性能的试验研究及分析

以桑塔纳2000AJR发动机为研究对象,在原有的汽油机基础上,增加了一套双燃料燃气喷射系统后,改为汽油／液化石油气两用燃料发动机。在几个工况下,对汽油与液化石油气的动力性能、经济性能以及排放性能进行对比,结果表明：在原有汽油机结构参数不变的情况下,燃用液化石油气时动力性能较原有汽油机有所下降,但是经济性能、排放性能有所提高。     

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。     

LPG-汽油双燃料发动机试验研究

选用澳华液化石油气（LPG）有限公司生产的汽车用石油气燃料供给管理配于EQ6100－I型发动机，改装成LPG－汽油双燃料发动机，进行性能测试分析。试验结果表明，在不改变原机压缩比和点火提前角时，燃用液化石油气的动力性下降，最大功率为原机的90％；最大扭矩为原机的92％。燃用LPG比燃用汽油的当量比油耗低，节能率在5％左右。怠速排放试验表明，燃用LPG的CO，HC排放浓度分别为燃用贩50％和36％。     

液化石油气—柴油双燃料发动机的试验研究

液化石油气比其它气体燃料热值高又便于储存运输。它是一种优良的民用燃料,也是点燃式发动机理想的代用燃料。由于各种原因,我国在车辆上使用液化石油气的工作开展不广。为了更合理有效地利用液化石油气资源,作者探索在柴油发电机组上燃用液化石油气,将柴油机改装成液化石油气-柴油双燃料发动机。本文介绍了这种发动机双燃料供给系统的方案以及在2135柴油发电机组上进行试验的情况。     

小型发动机燃用汽油、乙醇和LPG燃料的排放对比

对125mL发动机燃用汽油、乙醇和液化石油气(LPG)时的过量空气系数和点火提前角与排放性能之间的关系进行了试验研究．指出了影响这三种燃料发动机排放性能的敏感参数的合理取值范围．通过对比试验，验证了发动机燃烧乙醇可降低NOx排放浓度．发动机燃烧LPG时，低HC排放的空燃比范围比其它两种发动机空燃比范围广．研究结果可为小型汽油、乙醇和LPG发动机参数匹配提供参考。     

LPG-汽油双燃料发动机试验研究

选用奥华液化石油气有限公司生产的汽车用石油气燃料供给装置配于EQ6100-I型发动机进行性能测试分析.试验表明,在不改变原机压缩比和点火提前角时,燃用LPG的动力性下降了,最大功率为原机90%;最大扭矩为原机的92%.燃用LPG比燃用汽油的当量比油耗低,节能率在5%左右.     

二甲醚柴油混合燃料D40燃烧与排放的试验研究

通过在4100QBZL柴油机上进行燃用柴油以及柴油和二甲醚混合燃料——D40的试验,对比了动力输出、排放和缸内燃烧的数据,分析了D40燃料的燃烧特性与排放性能,改变供油系统参数进一步优化了燃用D40的排放性能。结果表明：柴油机供油系统调整后燃用D40燃烧特性好,可获得良好的动力性能,碳烟排放降低明显,NOx在中高转速下显著降低,预混燃烧阶段的温度是影响二甲醚柴油混合燃料NOx排放的主要因素。     

Fuel conversion efficiency of a port injection engine fueled with gasoline–isobutanol blends

This paper describes the comparative advantages of using isobutanol as a fuel for SI (spark ignition) engines instead of ethanol. An experimental study of fuel conversion efficiency was performed on a port injection engine fueled with mixtures containing 10, 30 and 50% isobutanol blended with gasoline. Efficiency as well as performance levels were maintained within acceptable limits for all three types of fuel blends compared to running the engine on straight gasoline. These results show that isobutanol is an attractive drop-in fuel for SI engines, and can be blended with gasoline in much higher concentrations compared to ethanol, without any modifications to the fuel system or other engine components.     

Investigating the effects of LPG on spark ignition engine combustion and performance

A quasi-dimensional spark ignition (SI) engine cycle model is used to predict the cycle, performance and exhaust emissions of an automotive engine for the cases of using gasoline and LPG. Governing equations of the mathematical model mainly consist of first order ordinary differential equations derived for cylinder pressure and temperature. Combustion is simulated as a turbulent flame propagation process and during this process, two different thermodynamic regions consisting of unburned gases and burned gases that are separated by the flame front are considered. A computer code for the cycle model has been prepared to perform numerical calculations over a range of engine speeds and fuel–air equivalence ratios. In the computations performed at different engine speeds, the same fuel–air equivalence ratios are selected for each fuel to make realistic comparisons from the fuel economy and fuel consumption points of view. Comparisons show that if LPG fueled SI engines are operated at the same conditions with those of gasoline fueled SI engines, significant improvements in exhaust emissions can be achieved. However, variations in various engine performance parameters and the effects on the engine structural elements are not promising.     

丙酮-丁醇-乙醇(ABE)/汽油混合燃料对高速发动机性能影响的试验研究

以发动机4000r/min、节气门开度35%为试验工况,对纯汽油及不同掺混体积分数丙酮-丁醇-乙醇(acetone-butanol-ethanol,ABE)与汽油混合物开展了不同点火提前角和喷油量的试验研究。分析了不同ABE混合比、点火提前角和过量空气系数对发动机性能的影响,并对每种燃料发动机最大功率工况的性能参数进行了比较。结果表明：点火提前角和过量空气系数相同时,混合燃料中ABE含量越高,燃油流量越大,发动机功率越大,有效热效率越高;燃油流量的总热量增大和热-功转换效率提高是促使发动机功率增大的主要原因;随ABE掺混比增加,NO比排放明显降低,CO比排放略有增加,碳氢化合物比排放先增后减。浓混合气工况增加ABE含量比在当量空燃比状态下增加ABE含量,发动机的有效热效率增大更明显,发动机的NO比排放降低更加明显。研究表明高速汽油机掺混ABE燃料具有较好的应用前景。     

液化石油气与汽油燃烧特性的对比试验研究

在点燃式发动机上分别燃用液化石油气和汽油,通过采集示功图并进行放热规律计算,对两种燃料在相似工况、相同过量空气系数下的燃烧特性进行对比分析。结果表明,在不改变样机结构和点火提前角的情况下,燃用液化石油气造成样机最大输出功率下降了7.64%。标定工况下,过量空气系数的变化对样机燃用汽油时的功率影响较大。两种燃料标定工况下的比热耗均随过量空气系数的增大而降低,但液化石油气降低的幅度较小。相似工况、相同过量空气系数下,相对于汽油,液化石油气的滞燃期短,燃烧持续期短,燃烧速度快。     

Future fuels and mixture preparation methods for spark ignition automobile engines

Research in the automobile industry focuses on studies of spark ignition automobile engines especially of stratified charge engines, lean combustion concepts, engines fueled by alcohol/gasoline blends, alcohol engines, and engines with on-board gas generators fueled by a variety of liquid fuels. The goal of this work is the development of low-emission, high fuel-economy and high performance power systems for the early 1990s. The implementation of this objective makes it necessary for more information on future fuel characteristics. In addition proper mixture preparation methods must be applied to find solutions to specific problems such as NO_x formation and aldehyde emission, while maintaining good fuel economy and high engine efficiency. The goal of this paper is to discuss the most attractive approaches for improved preparation and distribution of the fuel-air mixture with respect to future fuels such as alcohol/gasoline blends and other alcohol fuels.     

汽油机燃用汽油-乙醇混合燃料的试验研究

本文针对摩托车汽油机燃用乙醇的应用研究，在汽油机结构不作变动的前提下，掺烧一定比例的工业乙醇，进行发动机台架试验。在节气门开度分别为25％、50％、75％及100％时，在不同转速和负荷下，对发动机的功率、扭矩、能耗率及排放性能进行了研究，并与原机进行比较。试验结果表明，燃用汽油一乙醇混合燃料可以提高发动机的动力性和经济性，有效改善排放特性。     

BUTANOL—A SINGLE CYLINDER ENGINE STUDY: ENGINE PERFORMANCE

The effect of methanol and butanol addition to gasoline on brake specific fuel consumption (b.s.f.c.), exhaust gas temperature, and thermal efficiency has been experimentally investigated. A Hydra single cylinder, spark ignition, fuel injection engine was used over a wide range of fuel/air equivalence ratio (ϕ=0⋅8 to 1⋅3) for 30% volume alcohol–gasoline blends. The goal of this work is to study the engine performance when methanol and butanol–gasoline blends are used. The performance measurements show that there is an increase in b.s.f.c. when using alcohol–gasoline blends, and b.s.f.c. of a butanol–gasoline blend is less than for a methanol–gasoline blend. The experimental results show that the engine thermal efficiency was decreased when fueled with alcohol–gasoline blends. It was found that there was about a 4.5% reduction in engine thermal efficiency at ϕ=1⋅0 when 30% butanol was blended with gasoline compared to pure gasoline. The exhaust gas temperature measurements show that there is an increase in temperature in the case of using gasoline as compared to alcohol–gasoline blends, and that the temperature reaches a maximum at ϕ≈1⋅1 when using gasoline and alcohol–gasoline blends. © 1997 by John Wiley & Sons, Ltd.     

小型点燃式发动机应用LPG的微粒排放特性

介绍了液化石油气(LPG)在点燃式发动机上应用时微粒排放特性的试验研究．试验在一台四行程、水冷125mL单缸电喷式发动机上进行．结果表明,LPG在点燃式发动机上应用时也有大量的微粒排放,但其排放的总颗粒数与使用汽油燃料时基本相同．LPG燃料排放的微粒在粒度分布上有双峰分布的特点,但有时第1个峰的特征不明显,第2个峰对应的粒径大小同汽油机基本相同,发动机中等负荷时的微粒排放量最大,浓混合气的微粒排放量高,微粒的粒数浓度在中等转速时最大。     

利用快速压缩膨胀机研究火花点火LPG发动机的燃烧过程

利用快速压缩膨胀机对火花点火LPG发动机的燃烧过程进行了模拟与测量，分析了混合气浓度，点火提前角，压缩比以及燃烧室形状等对LPG燃烧过程的影响，可供汽油机改装成汽油／LPG双燃料发动机的参考。     

混氢对怠速工况发动机循环变动和排放的影响

针对汽油机怠速时循环变动大、排放高的问题,在一台加装了电控氢气喷射系统的1.6L汽油机上就混氢对发动机怠速性能的影响进行了试验研究。在怠速条件下,通过自主开发的电子控制单元调整氢气与汽油的喷射脉宽,使进气中混氢体积分数从0%逐渐增加至6.52%,同时减少汽油的喷射脉宽,以保证混氢后发动机仍工作在理论过量空气系数条件下。试验结果表明,混氢后发动机火焰发展期和快速传播期缩短;平均指示有效压力的循环变动系数由原机的9.97%减少至混氢体积分数为6.52%时的4.93%。NOx排放随混氢分数增加而减少;在混氢体积分数小于4.88%时,HC与CO随混氢比的增加而减少,但当混氢分数大于4.88%时,HC与CO排放再次升高。