同質與異質燃料在衝擊式霧化裝置的霧化情形與燃燒現象(水/乙醇/煤油)

Spray Phenomenon and Combustion of Like and Unlike Impinging Jets (Water/Ethanol/Kerosene)

潘建豪(Chien-Hao Pan)

指導教授 ： 王興華

國立臺灣大學/工學院/機械工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.00685

摘要

本實驗是利用衝擊式霧化與鈍體燃燒器的概念應用到燃燒方面，將兩種異質燃料(乙醇、煤油)直接互相撞擊霧化燃燒，節省過去一般液態燃料霧化燃燒需要提前預混的步驟；在燃燒之前先了解雙液柱撞擊的現象，確保撞擊後的液膜皆可達到開放液膜使撞擊後產生的霧化液滴粒徑較小，減少燃燒時間；接著進行燃燒實驗，利用液柱速度的改變調配乙醇與煤油的流量比例，以及調整駐焰環高度、環型空氣量大小，觀察火焰高度變化與火焰焰色、結構，初步了解相互的關係與燃燒狀況，並加入當量比進行討論。

實驗結果顯示隨著環型空氣量的增加其當量比越低，火焰高度也會降低，表示燃料與空氣的比例接近貧油燃燒，燃燒效率越好；火焰焰色方面加入乙醇比例越多，火焰焰色越暗，表示增加乙醇流量將有助於減低soot的產生；而增加駐焰環高度使環內產生較大的迴流區將有利於異質油料的混合，增加燃燒效率。

關鍵字

衝擊式霧化 ； 鈍體燃燒器 ； 霧化燃燒 ； 火焰

並列摘要

This experiment use of impinging jets atomization device and bluff-body burner concepts applied to combustion, two different fuels (ethanol, kerosene) mutual impingement spray combustion directly, skip the premixed process that liquid fuels spray combustion of general steps; To understand the phenomenon of double impinging jets of liquid fuels, ensure that the liquid sheets can be reached open rim after impinging jets caused droplet size smaller, reduce the burning time; And then continue the combustion experiment that using jets velocity change flow rate ratio of ethanol and kerosene, adjust flame-holder height and ring-size air flow rate, and then observe flame height, color and structure, initial understanding of mutual relations and combustion conditions, and then join the equivalence ratio to discuss.

Experimental results display as increasing ring-size air flow rate more, the equivalent ratio and flame height more low, it mean that fuels and air proportion close to fuel-lean, and combustion efficiency increased; Flame color aspects joined ethanol proportion more, flame color more dark, it mean that increased ethanol flow will helps reduce soot of produced; And increased flame-holder height to produced larger recirculation zone, it can increase mix efficiency of heterogeneous fuels and combustion efficiency.

並列關鍵字

Impinging Jets Atomization ； Bluff-Body Burner ； Spray Combustion ； Flame

參考文獻

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