碩士生: 安多卡 (印尼籍)
畢業年分: 2023年7月
論文名稱: 氫氣添加對一氧化二氮−乙烯逆擴散火焰生成之煙粒的影響(中文) / Effect of hydrogen on soot formation in a nitrous oxide − ethylene inverse diffusion flame (英文)
中文摘要:
本研究探討在一氧化二氮–乙烯（N₂O–C₂H₄）逆向擴散火焰中，氫氣摻混比例（0–20%）對煙灰生成的影響，並運用先進雷射診測技術進行分析。CH* 螢光用於量測火焰高度與反應區，雷射誘導白熾（LII）與平面雷射誘導螢光（PLIF）則分別測得煙灰強度與甲醛（CH₂O）濃度。
實驗結果顯示，火焰高度約維持在5 cm，但隨氫氣比例提升縮短約3 mm。與氦氣相比，氫氣更有效抑制煙灰生成，歸因於 CH* 與 C₂* 螢光增強所導致的反應途徑改變。雖然火焰溫度隨氫氣增加而上升，煙灰濃度卻持續下降，顯示氫氣對逆火焰具顯著減煙效果。排放分析結果指出，氫氣摻混會改變污染物生成機制，高氫條件下 NO 增加而 NO₂ 減少，反映溫度對 NOx 路徑的影響；同時 CO 排放隨氫氣提升而下降，代表燃燒更趨完全。綜合而言，氫氣摻混能有效降低煙灰並改善燃燒特性，對於發展低排放燃燒技術具有應用價值。
英文摘要:
This thesis examines the effects of hydrogen enrichment (0–20%) on soot formation in nitrous oxide–ethylene (N₂O–C₂H₄) inverse diffusion flames using advanced laser diagnostics. CH* chemiluminescence was applied to determine flame height and reaction zones, while laser-induced incandescence (LII) and planar laser-induced fluorescence (PLIF) measured soot intensity and formaldehyde (CH₂O) concentration.
Results show a consistent flame height of about 5 cm, though increasing hydrogen enrichment shortened the flame by approximately 3 mm. Compared with helium dilution, hydrogen was more effective in suppressing soot, attributed to enhanced CH* and C₂* chemiluminescence that modified flame reaction pathways. Despite elevated flame temperatures, soot concentrations decreased steadily with greater hydrogen content, highlighting hydrogen’s capacity to mitigate soot formation in inverse flames.
Emission analysis revealed that hydrogen enrichment significantly influenced pollutant formation. Higher hydrogen levels resulted in increased NO but reduced NO₂, reflecting the role of temperature on NOx pathways. Meanwhile, CO emissions declined with enrichment, indicating improved combustion completeness.
In summary, hydrogen enrichment effectively suppresses soot formation in inverse N₂O–C₂H₄ diffusion flames while altering flame structure and emission characteristics. These findings support hydrogen’s potential as a cleaner combustion strategy for future low-emission energy systems.
