Lean burn combustion of natural gas in spark-ignited engines is a promising approach to improving engine performance and efficiency by reducing pollutant emissions and better fuel consumption. However, inducing excessive lean mixture to the engine makes the combustion unstable, and misfire happens in a significant number of cycles. The pre-chamber ignition technology is a useful solution that can make spark-ignition engines more efficient. In this study, the lean mixture's combustion was empirically investigated with a new pre-chamber spark plug in a one-cylinder engine fueled with natural gas. Tests were performed at 11.5, 13.5, and 16 compression ratios and a wide range of air-fuel ratios. With the pre-chamber spark plug usage, the lean operating limit is enlarged by 10%–45% and gives 4% and 3% the average lower in-cylinder pressure and exhaust gas temperature than the conventional spark ignition system. The brake-specific fuel consumption was improved by 4%–11% using the pre-chamber spark ignition. The HC, CO, and NOx formation is about 11%, 16.3%, and 10% lower than the conventional spark ignition usage. Outcomes confirmed that the new design pre-chamber plug gives 1% improved COV_IMEP than the standard spark plug. The use of pre-chamber due to the lean-burn combustion causes larger ignition delay and increases brake thermal efficiency by up to 9%. It can be concluded that the pre-chamber increases the ignition ability, and the lean mixture limit is extended.

中文翻译：

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通过使用新的预燃室改善稀薄燃烧气体燃料火花点火发动机的性能和排放

火花点火发动机中天然气的稀薄燃烧是通过减少污染物排放和更好的燃料消耗来提高发动机性能和效率的一种有前途的方法。然而，将过多的稀混合气引入发动机会使燃烧不稳定，并且在大量循环中会发生失火。预燃室点火技术是一种有用的解决方案，可以提高火花点火发动机的效率。在这项研究中，在以天然气为燃料的单缸发动机中，使用新的预燃室火花塞对稀混合气的燃烧进行了实证研究。测试在 11.5、13.5 和 16 的压缩比和宽范围的空燃比下进行。随着预燃室火花塞的使用，与传统火花点火系统相比，稀燃操作限制扩大了 10%–45%，使缸内压力和废气温度平均降低了 4% 和 3%。使用预燃室火花点火，制动特定燃料消耗提高了 4%–11%。HC、CO 和 NOx 的形成比传统的火花点火使用低约 11%、16.3% 和 10%。结果证实，新设计的预室塞使 COV 提高了 1%_IMEP比标准火花塞。由于稀薄燃烧而使用预燃室会导致更大的点火延迟，并将制动热效率提高高达 9%。可以得出结论，预燃室提高了点火能力，延长了稀混合气极限。