相向噴流衝擊擴散火焰

A study on Jet Impinging Flame

溫明晃(Ming-Houng Wen)

指導教授 ： 蘇艾

元智大學/工程學院/機械工程學系/碩士(1998年)

摘要

本實驗主要在研究噴流衝擊火焰燃燒結構，藉由控制噴嘴角度、燃料流量和氮氣與甲烷體積比來觀察火焰結構變化。運用燃氣間對衝所造成停滯面做為火焰的駐燃機構，較單純擴散火焰燃燒效率及昇溫能力好，並且可短化火焰長度，但在燃氣對衝時火焰根部下方會產生高溫回火區。在不同雷諾數下燃氣速度增加時火焰衝擊點溫度會降低，火焰升溫能力較強而火焰高度也隨之增加。
近似預混火焰燃燒中火焰燃燒較好，燃料的燃燒較完全，減少燃料不完全燃燒而產生的碳粒子。隨著氮氣與甲烷體積比的增加，火焰長度會縮短，火焰藍色預混貧油區比例增加，並且火焰內部溫度分布較為均勻。燃燒器角度不同時，雖然對火焰內部溫度分布影響並不大，但對於火焰的回火區造成很大的影響，隨著角度的增加回火區越來越明顯。

關鍵字

噴流火焰 ； 衝擊火焰 ； 擴散火焰

並列摘要

The structures of the jet impinging flame are observed under different impinging angles, Renolds number and fuel dilution. The impinging flame of methane fuel is therefore constructed at the stagnation plane. This simple mechanism may reduce the combustion length and the combustion efficiency. But there is a high temperature flashback in the root of flame. When the Renolds number increase, the temperature of impinging flame reduce at the stagnation point and the combustion efficiency increase.
Along with the ration of volume nitrogen and volume methane, the combustion length is reduced and the blue proportion of flame is increased. The temperature distribution of flame is uniform, too. Along with the impinging angle is increased, the area of flashback in the root of flame obvious more and more.

並列關鍵字

impinging flame ； quasi-premixed flame ； diffusion flame

參考文獻

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