Abstract: This study establishes a single-cylinder model of a dual-spark-plug methanol engine based on a three-dimensional computational fluid dynamics (CFD) simulation platform. Through simulation methods, it analyzes in detail the effects of different dual-spark-plug configurations on the combustion and emission performance of high-compression-ratio methanol engines. The results indicate that the peak cylinder pressure, heat release rate, and temperature all show a trend of first increasing and then decreasing with the increase of A (the ratio of dual spark plugs to cylinder diameter). Specifically, the peak cylinder pressure at A=0.4 is approximately 15.69% higher than that at A=0.8, and the peak heat release rate at A=0.4 is about 13.5% and 39.11% higher than those at A=0.2 and A=0.8, respectively. At A=0.4, the engine achieves the lowest unburned methanol, formaldehyde, and SOOT emissions, while the NOx emissions reach the highest. Overall, the engine exhibits optimal performance at A=0.4, characterized by higher combustion efficiency and favorable emission characteristics, whereas A=0.8 is the least ideal dual-spark-plug configuration.

Key words: dual spark plug; high compression ratio engine; methanol; engine performance

摘要： 该研究基于三维计算流体力学（CFD）仿真平台，建立双火花塞甲醇发动机单缸模型。 通过模拟仿真的方法，详细分析了不同双火花塞布置对高压缩比甲醇发动机燃烧与排放性 能的影响。研究结果表明，峰值缸压、放热率及温度均随 A（双火花塞与气缸直径之比）的 增加呈现先增大后减小的趋势，其中 A=0.4 的峰值缸压比 A=0.8 高约 15.69%、峰值放热率比 A=0.2 和 A=0.8 高约 13.5％和 39.11％。在 A=0.4 时，具有最低的未燃甲醇、甲醛和 SOOT 排 放量，同时 NOx 排放量达到最高。综合来看，A=0.4 时的发动机性能最佳，表现为更高的燃 烧效率与最佳的排放特性，A=0.8 是最不理想的双火花塞布置方案。

关键词: 双火花塞；高压缩比发动机；甲醇；发动机性能