共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
均质充量压缩点燃着火HCCI(Homogeneous Charge Compression Ignition)作为内燃机新型燃烧方式。具有高效、低排放燃烧的巨大优势,为汽油机性能的提高提供了广阔前景。文中基于化学反应模拟软件Chemkin,利用九区模型模拟了甲烷的HCCI燃烧过程,分别讨论了进气压力、进气温度、压缩比和燃空当量比对甲烷HCCI燃烧的影响。 相似文献
3.
在设计未来的汽油机时,均质充量压燃(HCCI)堪称为理想的燃烧方式。但目前HCCI燃烧方式仅限于低转速、中低负荷区域,并有待拓展其运行范围。目前,大部分汽油机仍在采用火花点燃(SI)燃烧方式。介绍了一种构想,鉴于HCCI燃烧还不能在所有发动机运行条件下实现,在高负荷及高转速条件下仍要采用SI燃烧方式,因此建议应用SI燃... 相似文献
4.
在往复式发动机中,除了火花点燃式燃烧和柴油压燃燃烧的运转方式外还有第3种运转方式,即均质充量压燃燃烧(HCCI).HCCI模式发动机的运转情况被认为是高效和稳定的。在部分负荷工况下可以大幅度降低NOx的排放.把HCCI燃烧应用到发动机方面尽管仍有一些困难.但HCCI燃烧方式表明在发动机应用的巨大替力,本文将阐述HCCI与传统发动机燃烧方式的不同及其未来的展望。 相似文献
5.
介绍利用光谱测试方法对均质充量压缩着火(HCCI)的燃烧特性进行分析的实例。分析结果显示,一定波长的消光系数与低温氧化反应的活性程度有关,相关知识将对解释HCCI燃烧的机理有所帮助。 相似文献
6.
7.
8.
9.
随着现代汽车对发动机动力性和尾气排放标准的要求越来越高,压缩点燃和火花点燃这2种传统燃烧概念的局限性也越来越明显,于是内燃机研究人员提出了一种新的内燃机燃烧概念——均质充量压缩点燃(HCCI)。 相似文献
10.
本文简要介绍了发动机均质充量压缩着火(HCCI)燃烧的概念和特点,并进一步着重分析了柴油机HCCI燃烧的特点,以及影响柴油机HCCI燃烧的一些重要因素,如混合气形成方式、进气温度、负荷、废气再循环(EGR)、气门正时及压缩比等因素。 相似文献
11.
13.
J. Kim J. Jang K. Lee Y. Lee S. Lee S. Oh 《International Journal of Automotive Technology》2014,15(2):183-189
Recently, biodiesel has emerged as an alternative fuel for achieving low-temperature combustion (LTC). Several articles in the literature have showed that oxygenated biofuels, including biodiesel, can improve combustion stability under high exhaust gas recirculation (EGR) operation, which is considered to be necessary for the removal of nitric oxides (NOx). The objective of this study was to investigate the performance and emissions of 20% biodiesel blended diesel fuel (B20) at various intake pressures and oxygen concentration levels to characterize the fuel for LTC application. The experimental investigation of B20 was carried out using a single-cylinder engine (SCE) at 1400 rpm and 50% load condition. A set of critical flow orifices with synthetic EGR was employed to simulate various intake pressures and EGR levels. The behavior of the B20 was first characterized under various intake conditions. The results showed that with high oxygen intake, B20 exhibited combustion and emission levels that were very similar to conventional diesel. However, B20 reduced combustion deterioration while exhibiting lower carbon monoxide (CO) and hydrocarbon (HC) emissions than diesel under low oxygen intake conditions. 相似文献
15.
6月5日,成都发生公交车纵火案件,造成重大人员伤亡;6月13日,广东深圳一辆公交车发生自燃,短短10几分钟,车子只剩下一具残骸;6月15日,江苏常州市一辆BRT快速公交车发动机舱突然冒烟起火,所幸司机发现及时措施得当,并没有引发大火;6月17日浙江舟山13路空调车发动机部位起火,5分钟内整辆车全部被大火吞噬,烧的只剩下骨架。一时间人们谈“公交车”色变。 相似文献
16.
电动汽车的时代也许还要20年才能到来,目前的时间仍然是内燃机的时代,但我们可以看到内燃机却已是强弓之末。因为即便是再先进的内燃机,仍然需要消耗化学能,需要排放。 相似文献
17.
18.
本文介绍AVL公司研制的AVL高速照相摄影装置及其使用方法。此法应用内窥镜进行燃烧过程高速照相。这是一种简便可行又实用的燃烧测试方法。本文对研究燃烧过程有参考价值。 相似文献
19.
T. Fang R. E. Coverdill C. -F. F. Lee R. A. White 《International Journal of Automotive Technology》2009,10(3):285-295
In this paper, the influence of injection parameters on the transition from Premixed Charge Combustion Ignition (PCCI) combustion
to conventional diesel combustion was investigated in an optically accessible High-Speed Direct-Injection (HSDI) diesel engine
using multiple injection strategies. The heat release characteristics were analyzed using incylinder pressure for different
operating conditions. The whole cycle combustion process was visualized with a high-speed video camera by simultaneously capturing
the natural flame luminosity from both the bottom of the optical piston and the side window, showing the three dimensional
combustion structure within the combustion chamber. Eight operating conditions were selected to address the influences of
injection pressure, injection timing, and fuel quantity of the first injection on the development of second injection combustion.
For some cases with early first injection timing and a small fuel quantity, no liquid fuel is found when luminous flame points
appear, which shows that premixed combustion occurs for these cases. However, with the increase of first injection fuel quantity
and retardation of the first injection timing, the combustion mode transitions from PCCI combustion to diffusion flame combustion,
with liquid fuel being injected into the hot flame. The observed combustion phenomena are mainly determined by the ambient
temperature and pressure at the start of the second injection event. The start-of-injection ambient conditions are greatly
influenced by the first injection timing, fuel quantity, and injection pressure. Small fuel quantity and early injection timing
of the first injection event and high injection pressure are preferable for low sooting combustion. 相似文献
20.
随着经济的发展,汽车逐渐普及,汽车自燃因危害巨大,越来越受到人们的关注。本文系统地分析汽车自燃的原因,并阐述了五个方面的预防措施,以及发生自燃后,如何紧急处理减少损失。 相似文献