【作者】 张跃华；

【导师】 周丛钜；

【作者基本信息】 广西大学 ， 农业机械化工程， 2001， 硕士

【摘要】 本文首先从理论上阐述了乳化油的节能降污机理，指出了柴油机燃用不 稳定乳化油的可能性，并根据不稳定乳化油的特性，以N485Q直喷式柴油机 为研究对象，设计了四种不同结构的随车乳化器（该乳化器不必添加乳化剂， 动力能耗小，能将柴油边乳化边燃烧），并通过各种不同配比乳化油的稳定 时间及其粘度──温度特性试验，确定了在该N485Q柴油机上使用的最佳随 车乳化器；接着，按照国标GB3847－1999《压燃式发动机和装用压燃式发动 机的车辆可见污染物限值及测试方法》，考察该N485Q柴油机在原机结构参数、 最佳随车乳化器条件下，最大扭矩转速 （180r/min）和最大功率转速（2300 r／min）处燃用不同油水配比乳化油时的节能降污（燃油消耗率、排气烟度、 排气温度）效果，找出乳化油的最佳油水配比；然后，为了更进一步考察该机 燃用最佳随车乳化器制备的最佳配比乳化油的节能降污效果，设计了二因素二 次正交回归旋转试验，建立最大功率转速 （2300 r／min）处不同负荷（12．68kw、 16．90kw、21．30kw）时的发动机结构参数──静态供油提前角、喷油压力的 燃油消耗率回归方程，运用外点惩罚函数法分别对三个方程进行优化，得出各 自理论最小燃油消耗率及其结构参数，再调定发动机结构参数至各自燃油消耗 率方程的理论值，通过试验得出其实际燃油消耗率，并将燃油消耗率理论值与 试验值误差最小的结构参数调整作为燃用最佳配比乳化油时的结构参数调整； 最后，进行发动机结构参数作调整情况下燃用最佳随车乳化器制备的最佳油水 配比乳化油时的外特性试验，并与该机原结构参数条件下燃用纯柴油时的外特 性试验作比较，综合考察该种乳化油的节能降污效果。在试验结束后，还对乳 化油是否对气缸有腐蚀和加剧气缸磨损等负作用进行了考察。 试验结果表明，该N485柴油机在燃用4号随车乳化器配制的油水配比为 12％的乳化油条件下，当静态供油提前角调至23．0℃，喷油压力调至12．32Mpa 时，有最好节能降污效果，其节油率范围为1．9～4．3％，烟度下降范围为 19．1～21．8％，排气温度下降范围为11～15℃（可认为NO_x排量下降），但此 时发动机的最大功率有所下降，降幅为4．71～9．52％，且由于水的加入使柴 油中硫分转变为亚硫酸根(SO₃^2-)或硫酸根(SO₄^2-)的机率增大，表现为气 缸中点蚀现象增多。另外，水的掺入未对气缸产生冲刷作用，因此不会对气缸 造成额外的磨损．更多还原

【Abstract】 This thesis firstly elaborated the saving energy and reducing pollutants mechanism of emulsified fuel in theory, pointed out the possibility of burning with unsteady emulsified fuel in diesel engine. On the basis of the character of unsteady emulsified fuel, regarding N485Q DI diesel engine as the object of study, 4 emulsifiers with different structure, which needn’t add fuel additive, can burn as emulsifying and whose energy is small was designed. Then the best emulsifier which was used cooperatively with the engine was selected through the steady time of emulsified fuel of all sorts of ratio of water addition in fuel and also through the experiment of viscosity ?temperature. Secondly, according to Nation Standard. GB3847-1 999, Limits and measurement methods of exhaust visible pollutants from compression ignition(C .I.)engines and vehicles equipped with CI. engines, the saving energy and reducing pollutants study including fuel consume ratio, emission smoke and emission gas temperature was done at the rotational speed at maximum torque(1800r/min) and rotational speed at maximum power(2300r/min) on the condition of the structure parameter of original numerical of the engine and the best emulsifier, then the best ratio of water in diesel was found out. Thirdly, in order to study more deeply on the engine with its saving energy and reducing pollutants effect on the condition of burning with emulsified fuel of the best ratio of water in diesel, an experiment were developed by the rotate design of positive intersection of 2 operating parameters(injection advance angle and injection pressure) on the different load (12.68kw,16.9Okw,21.3Okw) of the rotation speed at maximum power(2300r/min). The equations about fuel consumption were set up and their minimum fuel consumption and structure parameters in theOry were calcuated through the opbeation design with methodof exterior penaity boction. T’hell, the engine sane parameterswere adjusted to the theoretical vaiues and the practical vaiues of itsfuel consumption would be given. The minhoum errors of the fuelconsumption between theoretical value and practical value would beregarded as the using value. Finally, a velocity characteristiceXPeriment wun full load was dOne under the adjusAnen of enginesmicfore parameters, and the olltcome was contrasted with theoutcome of the engine buming with the pure diesel on the conditionof its original StrUCtUe parameters. At the end of the exPerhaent, aninVestigation on Whether baming emusified fuel would havenegative effects, such as cormPt and extra wear on cylindef, wouldbe had.The research results showed that this N485Q D.I. diesel enginewould have the best effect of saving energy and reducing pollutansWhen it bumed with the emusified fuel, which was equipped by theNO. 4 emulsifier and Whose ratio of water to emulsified fuel was l2%.By this, it’s range of saving diesel was 1.9~4.3%, range of reducingsmoke emission was l9.l -- 21.8%,and range of reducing gasemission temPeratue was l l ~ 15 oC (It was thought that the emissionof NOxreduced). But at the same tAne, the maxhaUIn power of thisengine reduced and its reducing range was 4.7l --9.52%, also therewere more dot-cormPt on cylinder wall because that plltting waterinto diesel led to more chances of element S tw into SO,’- andSO.’-. Moreovef, pnding watCr into diesel wouldll’t lead to theaction of flushing cylindet, so there wouldn’t be any extra wear ofcvlinuer更多还原