预燃式定容燃烧弹的研制与喷雾特性研究

Design of Constant Volume Pre-combustion Cell and Study on Spray Characteristics

相对于其他类型的喷雾燃烧实验装置,预燃式定容燃烧弹可以较好地模拟压燃式发动机燃油喷射瞬时缸内的环境热氛围。该文所研制的定容燃烧弹燃烧腔的体积为0.72L,可视化窗口直径为90mm。火花塞点燃乙烯、氧气和氮气的预混合气,可在定容燃烧弹内产生最高20MPa的高温高压环境。基于所研制的定容燃烧弹并结合高速摄像系统,可使用阴影法、米氏散射法等多种光学诊断方法对燃料的非蒸发喷雾、蒸发喷雾和不同氧气浓度条件下喷雾燃烧进行研究。

Constant volume pre-combustion cell （CVPC） can better simulate the high temperature and pressure environment of compression ignition engine compared with other spray and combustion apparatuses. The CVPC designed in this paper has a 0.72L combustion chamber in volume and 90mm optical window in diameter. When ignited the mix- ture of ethylene, oxygen and nitrogen in the chamber, it can provide a pressure as high as 20MPa. Combined with the CVPC and high speed imaging system, non-evaporation spray, evaporation spray and different oxygen concentration combustion progress could be recorded with shadowgraph, Mie-scattered and other optical diagnostic methods.