• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >High-speed fuel and flow imaging to investigate misfires in a spray-guided direct-injection engine.
【24h】

High-speed fuel and flow imaging to investigate misfires in a spray-guided direct-injection engine.

机译：高速燃油和流量成像可研究喷雾引导式直喷发动机的失火。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Simultaneous high-speed fuel fluorescence and particle image velocimetry measurements are combined with spark discharge measurements for the first time to identify the cause of misfire and partial burn cycles in a spray-guided spark-ignited direct-injection engine. Spark ignition is studied for stratified charge operation under a range of external dilution levels (0% - 26% nitrogen). Available spark energy is characterized for a wide range of well-controlled homogeneous gas-phase fuel-air mixtures (phi) = 0.0 - 2.9) and flow conditions (|V| = 1 - 10 m/s) that are characteristic for the spark energy under stratified charge conditions. Under stratified charge conditions, the engine operates with an optimized end-of-injection and spark timing that provides stable engine operation with the occurrence of rare misfire and partial burn cycles. Fuel concentration and flow field measurements are analyzed closest to the spark plug and in the entire field of view (38 mm x 30 mm) within the combustion chamber to diagnose the role of fuel distribution, flow field, and spark energy on misfire, partial burn, and well-burning cycles. Results show that abnormal spark behavior is not the cause of the misfire and partial burn cycles and a model is used to show that all cycles have sufficient electrical spark energy to ignite the flammable mixture nearby the spark plug. The high-speed fuel and flow images reveal that a flame kernel is developed for all cycles. For all errant cycles, flame propagation is too slow due to either lean and/or diluted mixtures and the flame kernel is not able to catch up to the fuel cloud that travels away from the spark plug. As a result, the flame kernel is surrounded by lean fuel-air mixtures that are insufficient to further support adequate flame kernel growth, leading to a misfire or partial burn. This work demonstrates the increased need for precise fuel injection and atomization control as well as consistent in-cylinder flow patterns that provide favorable mixtures for flame kernel development throughout the entire spark event.
机译：首次将同时进行的高速燃料荧光和粒子图像测速与火花放电测量相结合，以识别在喷雾引导的火花点火式直喷发动机中失火和部分燃烧循环的原因。针对外部稀释水平（0％-26％氮）范围内的分层装料操作，对火花点火进行了研究。可用的火花能量的特征是，在各种受控良好的均质气相燃料-空气混合物（phi = 0.0-2.9）和流量条件（| V | = 1-10 m / s）的情况下分层充电条件下的能量。在分层充气条件下，发动机以最佳的喷射结束和火花正时运行，从而在出现罕见的失火和部分燃烧循环的情况下提供稳定的发动机运行。在靠近燃烧室的整个视场（38 mm x 30 mm）内，分析最靠近火花塞的燃料浓度和流场测量值，以诊断燃料分布，流场和火花能量在失火，部分燃烧时的作用以及燃烧良好的周期。结果表明，异常的火花行为不是失火和部分燃烧循环的原因，并且使用一个模型来显示所有循环都具有足够的电火花能量，以点燃火花塞附近的可燃混合物。高速燃油和流量图像显示，在所有循环中都形成了火焰核。在所有不正确的循环中，由于稀薄和/或稀释的混合物，火焰传播太慢，并且火焰核无法赶上远离火花塞的燃料云。结果，火焰核被稀薄的燃料-空气混合物包围，该燃料-空气混合物不足以进一步支持适当的火焰核增长，从而导致失火或部分燃烧。这项工作证明了对精确燃料喷射和雾化控制以及一致的缸内流型的需求不断增长，这些模式为整个火花事件中的火焰核发展提供了有利的混合物。

著录项

  • 作者

    Peterson, Brian R.;

  • 作者单位

    University of Michigan.;

  • 授予单位 University of Michigan.;
  • 学科 Engineering Mechanical.
  • 学位 Ph.D.
  • 年度 2010
  • 页码 184 p.
  • 总页数 184
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号