柴油甲醇组合燃烧在工程机械上的研究及应用

发布时间：2018-06-24 12:04

  本文选题：柴油 + 甲醇　； 参考：《天津大学》2014年硕士论文

【摘要】：随着能源与环境形势的日益严峻,节能减排已成为一个世界性的热点问题。同样,我国作为世界级的汽车与能耗大国,2013年的石油表观消费量为5.14亿吨,石油进口量突破3亿吨,对外依存度达59.5%,因此,寻找内燃机替代燃料减少石油资源的消耗在我国显得尤为重要。甲醇作为一种燃料,在常温常压下呈液态,而且富氧、可再生,早已被证明可以应用在内燃机中。尤其是我国煤炭资源丰富,拥有巨大的甲醇产能,而石油资源紧缺,使得甲醇可以、也有必要成为我国内燃机替代燃料的理想选择之一。本课题组提出了柴油/甲醇组合燃烧(Diesel and Methanol Compound Combustion,DMCC)技术,成功地将甲醇应用在柴油机上,到目前为止已有十余年的经验积累。然而,我们过去的研究主要针对自然吸气式与增压中冷式发动机;应用则主要针对重型卡车,并未涉及采用增压非中冷发动机的非道路工程机械。因此,围绕DMCC技术在工程机械上应用的可行性及对其工作特性的影响,开展了本课题的研究。首先,本课题是在一台增压非中冷的典型工程机械发动机上进行部分改装,使其能够使用DMCC技术。并搭建试验台架,进行发动机纯柴油与DMCC两种燃油模式的试验对比、分析,研究DMCC技术对发动机性能的影响。其次,在台架试验得到满意结果之后,本课题结合先前的工作基础对矿山运输车与装载机进行了DMCC技术的应用改装;并通过实际运行考察工程机械使用DMCC的应用效果。台架研究表明,工程机械发动机在使用DMCC时,与纯柴油对比有如下不同:1)在燃烧特性方面,进气温度更低,平均降幅达6.2℃;最大放热率增大,平均增幅达44.2 k J/(m3°CA);爆发压力上升,负荷越大上升越明显,平均上升0.76MPa,升幅为6.8%。2)在动力性方面,外特性扭矩会出现2.8%的小幅下降;外特性功率与原机相比最大降幅为5.5k W、平均下降3.3k W,降幅2.1%。3)燃油经济性方面,甲醇对柴油的替代率平均能达30%左右;有效燃油消耗率降低,最大降幅为15 g/(k W·h),平均降幅为5.0 g/(k W·h),同比下降2.3%;有效热效率提高,平均增幅为0.87%。应用结果表明,工程机械DMCC应用的动力性增强,燃油经济性提高。以矿车为例,实况运行的替代率达35%,燃油成本下降24%。
[Abstract]:With the increasingly severe energy and environmental situation, energy conservation and emission reduction has become a worldwide hot issue. Similarly, as a world-class automobile and energy consuming country, China's apparent oil consumption in 2013 was 514 million tons, oil imports exceeded 300m tons, and its external dependence reached 59.55.Therefore, It is very important to find alternative fuels for internal combustion engines to reduce the consumption of petroleum resources in China. As a kind of fuel, methanol is liquid at room temperature and atmospheric pressure, and is oxygen-rich and renewable, which has been proved to be applicable in internal combustion engines for a long time. In particular, China is rich in coal resources and has a huge methanol production capacity. However, because of the shortage of petroleum resources, methanol can and is necessary to become one of the ideal alternative fuels for internal combustion engines in China. The diesel and method compound combustionc (DMCCs) technology has been put forward in this paper, and methanol has been successfully applied to diesel engines for more than ten years. However, our previous studies mainly focused on naturally aspirated and turbocharged intercooled engines, while the applications were mainly for heavy trucks, and did not involve non-road engineering machinery with turbocharged non-intercooled engines. Therefore, the feasibility of the application of DMCC technology in construction machinery and the influence on its working characteristics are studied in this paper. Firstly, a typical turbocharged non-intercooled construction machinery engine is partly modified to make it use DMCC technology. The test bench was set up to compare the two fuel modes of pure diesel and DMCC, and the effect of DMCC technology on engine performance was studied. Secondly, after the satisfactory results obtained from the bench test, the application of DMCC technology to mine transport vehicles and loaders has been modified on the basis of previous work, and the application effect of using DMCC in construction machinery has been investigated through practical operation. The bench study shows that when DMCC is used, the combustion characteristics of construction machinery engine are different from that of pure diesel oil as follows: (1) in terms of combustion characteristics, the inlet air temperature is lower, with an average decrease of 6.2 鈩，

本文编号：2061458