貧油預混火焰於陶瓷顆粒床燃燒特性

Combustion Phenomenons of Lean Premixed Flame in Ceramic Granular Bed

林士強(Shr-Chiang Lin) ； 楊授印(Shou-Yin Yang) ； 吳敏聖(Min-Sheng Wu) ； 徐德利(De-Li Hsu)

《燃燒季刊》 92期 (2016/02) Pp. 16-26

https://doi.org/10.30041/CQ.201602_(92).0002

摘要

化石能源大量使用，導致面臨能源短缺問題，因此本研究介紹一種高效能燃燒器，提升燃料的燃燒效率，達到節能目標。貧油預混CH_4/air、H_2/C_3H_8/air、C_3H_8/air燃氣於陶瓷顆粒床(Ceramic Granular Bed, CGB)燃燒，具有不同燃燒現象，因此本研究探討混合物流速(mixture velocity, ug)、當量比(equivalent ratio, ϕ)改變對火焰之影響。實驗選用5只熱電偶擷取的方式，從而觀察火焰溫度及絕對傳播速度(Absolute propagation speed, Sab)。結果顯示在CGB燃燒時，ug和發熱率通量(firing rate flux, Γ)的提升，導致火焰溫度及Sab增加；而Sab也隨ϕ提升而加速。在H_2取代C_3H_8燃料條件中，H_2濃度提升使Γ 略微減少，並且CGB熱傳現象的影響，導致溫度下降，同時擴大可燃極限。預混燃氣於陶瓷顆粒床燃燒，具有擴大可燃極限及提升燃燒效率的優點，有助於低熱值燃氣的應用。

關鍵字

貧油 ； 預混火焰 ； 顆粒床 ； 實驗

並列摘要

Due to extensive usage of fossil fuels, lack of energy become a issue now. Accordingly, a high efficiency burner is introduced in this study, improving combustion efficiency to achieve the goal of energy conservation. There are various combustion phenomenon of lean premixed CH_4/air, C_3H_8/CO/air and C_3H_8/air flame in Ceramic Granular Bed(CGB). Therefore, this study investigates the effect of mixture velocity (ug), equivalent ratio (ϕ) to observation of the combustion. Flame temperature and absolute propagation speed (Sab) are measured by five thermocouple in this experiment. The results exhibit that during combustion in CGB, ug and firing rate flux (Γ) is increase leading to the raise of flame temperature and Sab; In addition, Sab is accelerated with ϕ increase. In the H_2 substitution for C_3H_8 fuel conditions, and increase of H_2 concentration leads to the fact that Γ decrease slightly. Furthermore, the thermal conductive phenomenon in CGB result in a decrease of temperature and expansion of the lower flammable limit simultaneously. The premixed flame in CGB has advantages of expansion of the flammable limit and enhancement of the combustion efficiency, that assist the fuel gas application with the lower calorific value.

並列關鍵字

Lean ； Premixed flame ； Granular bed ； Experiment