本研究針對甲烷與氨氣混合燃料於對稱預混對沖流火焰中之燃燒行為進行數值模擬，透過數值模擬分析比對文獻數據驗證模擬數據可信度及完整性，探討不同混合比例與當量比對燃燒效率與污染物生成影響，由於氨氣具無碳特性，然而燃燒活性低且易產生NOx，因此本研究選用CHEMKIN-PRO軟體，模擬CH₄/NH₃比例自0%至100%、當量比=0.8、1.0、1.2之燃燒情況，結果模擬顯示，當CH₄/NH₃=70/30且=1.0時，可獲得最高火焰溫度（約2150K）、最完整的燃燒反應與最低NO生成量，為最佳操作條件，本研究亦對自由基分布、熱釋放率、反應路徑與NO生成機制進行分析，相關研究結果可作為未來發展以氨氣為替代燃料之低污染、高效率燃燒系統設計之參考，透過本研究建立之數值模擬分析流程與機制探討，未來可進一步應用於燃燒器優化設計、火焰穩定技術開發及NOx排放控制策略研擬，對於提升氨燃料應用可行性及推動潔淨能源技術具有實質助益。

This study numerically investigates the combustion behavior of methane–ammonia blended fuels in symmetric premixed counterflow flames. Numerical simulations were conducted and validated by comparing with literature data to ensure the reliability and integrity of the results. The effects of different blending ratios and equivalence ratios on combustion efficiency and pollutant formation were examined. Since ammonia is a carbon-free fuel but exhibits low combustion reactivity and tends to generate NOx, CHEMKIN-PRO software was employed to simulate combustion conditions with CH₄/NH₃ ratios ranging from 0% to 100% and equivalence ratios of 0.8, 1.0, and 1.2. The simulation results indicate that the optimal operating condition occurs at CH₄/NH₃ = 70/30 with an equivalence ratio of 1.0, yielding the highest flame temperature (approximately 2150 K), the most complete combustion reaction, and the lowest NO formation. Furthermore, this study analyzed radical distributions, heat release rates, reaction pathways, and NO formation mechanisms. The findings provide valuable insights for developing low-pollution and high-efficiency combustion systems utilizing ammonia as an alternative fuel. The numerical modeling approach and mechanism analysis established in this research can be further applied to combustor optimization, flame stabilization techniques, and NOx emission control strategies, contributing to the feasibility of ammonia fuel applications and advancing clean energy technologies.

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