本研究使用CHEMKIN配合GRI-Mech 3.0模擬不同二氧化碳比例添加至甲烷純氧燃燒的反應動力變化，利用化學反應式的淨反應速率搭配物質濃度變化排列出化學反應路徑，從反應動力學的觀點分析甲烷在高溫時，添加CO2至系統，主燃料消耗受到抑制之情形。經分析發現，大量的CO2添加會使得系統中的H、O及OH的濃度不斷降低，進一步的觀察發現CO+OH↔H+CO2反應式會隨著CO2大量的增加至系統而開始消耗H並且生成大量的一氧化碳，此一情形將會使得接續的H2+OH↔H+H2O淨反應速率下降，分歧反應O2+H↔O+OH與H2+O↔H+OH也相同減速進而使H、O及OH的數量降低。為求更完整的分析二氧化碳添加對甲烷純氧燃燒的影響，本研究也模擬及分析不同溫度的反應動力變化，隨著系統溫度在1200K以下，添加二氧化碳對於系統反應動力的影響將會逐漸降低。針對貧油狀態下，二氧化碳添加至甲烷純氧燃燒的反應路徑分析，甲烷及氧化物的分解仍會隨著二氧化碳加而同樣受到抑制。

Detailed kinetic modeling of pure oxygen combustion of methane has been performed to investigate the chemical effects of CO2 addition. GRI 3.0 mechanism is adopted in this modeling. The results show that CO2 addition significantly drops H and O peak concentrations at high temperatures (>1200K). Further analyses shows the reaction CO+OH↔H+CO2 consumes H atom with large amount of CO2 addition. This results the increase of the net rate of the reaction H2+O↔H+OH and H2+OH↔H+H2O, and the decrease of the net rate of the major chain branching reaction O2+H↔O+OH to cause the observed suppressing phenomena of the combustion reactions. With adding CO2, decrease reaction temperature reduces its kinetic effect on combustion process. At temperatures below ~1200K, the prohibition effect of CO2 on combustion process becomes insignificant. The effects of fuel lean condition on the kinetic modeling are presented that the inhibitions of CH4 and O2 decomposition still exist in the reacting system.

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