柴油燃料HCCI燃烧的稳定性研究

实现宽广负荷范围内的稳定燃烧是目前HCCI燃烧研究的热点之一．而HCCI燃烧在高、低负荷时的工作不稳定性是影响HCCI燃烧实用性的重要问题之一。在前期研究实现单缸柴油机HCCI燃烧的基础上，主要分析了发动机负荷和气门重叠期的变化对HCCI燃烧稳定性的影响，探讨了造成不稳定燃烧的原因。结果表明：HCCI燃烧在中间负荷燃烧稳定性最好，但在低负荷时容易产生失火，高负荷时容易产生燃烧压力振荡，造成不稳定燃烧；负气门重叠期增大有利于小负荷的燃烧稳定性，负气门重叠期减小有利于大负荷的燃烧稳定性。

Study on Stability of HCCI Combustion Operating with Diesel

The stable combustion over a wide load range is one of the key issues for HCCI combustion. In this paper, the diesel-fueled HCCI combustion was achieved. Based on the previous study, the combustion stability of HCCI combustion under various loads and valve timing intervals was investigated and the reasons for combustion instability were analyzed. The study showed that the best stability of HCCI combustion was achieved under the medium load. However, misfire cycle was easily occurring at low load and combustion pressure oscillation was observed at the high load, resulting in the combustion instability. Large negative valve timing interval would be beneficial to the improvement of combustion stability under low load whereas and small valve interval was favorable to the stability under high load.