彭杨茗，汪春梅，姚登举，李晶晶

（合肥工业大学 汽车与交通工程学院，安徽 合肥 230009）

    摘要: HCCI（均质充量压燃）发动机的燃烧过程主要是受到燃料本身的化学反应动力学控制，因此改变燃料的化学性质能够有效地控制HCCI发动机的燃烧过程。由于天然气不易压燃的化学特性，所以天然气HCCI发动机低负荷运行时，会因燃烧反应速率过慢而出现火焰温度低、燃烧不充分甚至“失火”等现象。本研究中，通过耦合详细天然气和臭氧（O₃）的燃烧反应机理，并结合HCCI单区模型，模拟计算了进气道添加O₃对天然气HCCI发动机燃烧相位的影响并进行化学反应路径分析。通过模拟计算与实验结果对比得出：进气道中添加10到40 ppm的O₃可以改变天然气的燃烧反应路径，实现对天然气HCCI发动机燃烧相位的控制。低浓度的O₃能有效地改变天然气低温燃烧时的燃烧相位并提高缸内燃烧压力，拓宽天然气HCCI发动机低负荷工况范围。

    关键词：均质充量压燃；天然气；臭氧；低温燃烧

Abstract：Thecombustion progress of HCCI （Homogeneous Charge Compression Ignition）engines is mainly governed by chemical kinetics of the fuels. Therefore, it is desirable to adjust the combustion progress by changing the chemical property of the fuels. As nature gas cannot be ignited easily by compression alone when HCCI engines run in low load condition, the low in-cylinder temperature leads to misfire. In this work，through the combination of the detail chemical kinetic mechanism of nature gaswith that of ozone in a single-zone model, the impact of O₃ on the combustion phase of HCCI engines were investigated, and the chemical reaction paths were analyzed. Comparing the calculated results with the experimental results，it reveals that chemical reaction paths of the nature gas can be changed by adding 10 to 40 ppm of O₃ into the intake port, to control the combustion phase of HCCI engines. Low concentration of O₃ can effectively advance the combustion phase of nature gas and improve the in-cylinder combustion pressure, which can extend the operational region of HCCI engines in low load conditions.

Keywords: HCCI; Nature Gas; Ozone; Low Temperature Combustion