雙組份柴油液滴於高溫環境下之燃燒現象觀察與研究

An experimental investigation on the burning charactistics of collision-merged diesel fuel droplets

孔令杰(Ling-Chieh, Kung)

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(2004年)

https://doi.org/10.6342/NTU.2004.01050

摘要

本實驗主要以Ink-Jet printing method產生穩定的雙自由液滴，經碰撞形成多組份液滴後，進入高溫燃燒爐，觀察液滴在各種撞擊條件的結合情況及燃燒特性。實驗中第一部分以高級柴油(Diesel Fuel, Premium Grade)、Methanol(CH3OH)與不可燃性液體Water（H2O）為主，在不同的液滴尺寸、比例下，觀察其燃燒現象，第二部份則將H2O與CH3OH以各種比例預混，產生不同體積濃度之CH3OH液滴後再與柴油做碰撞燃燒，與第一部份做比較。

實驗結果發現，H2O與柴油撞擊燃燒後會有水滴微爆與熄滅兩種情況，微爆出現機率與H2O的體積大小成反比。CH3OH與柴油撞擊燃燒會產生劇烈且不穩定的微爆。H2O與CH3OH預混部分，發現甲醇體積濃度變化會影響到撞擊液滴的結合形式，並影響到燃燒情況。

關鍵字

燃燒 ； 液滴 ； 微爆 ； 撞擊

並列摘要

Experiment applies Ink-Jet Printing method to generate dual free droplet streams and collided along their path as they fall. Then the collided droplets will fall into the combustion chamber freely and some collision states and burning characteristics are investigated. We use diesel fuel, methanol, and water in the first part of this experiment, and use diesel fuel and water-methanol-premixture in the second part. Then we will compare the results of these two parts.

According to the experiment results, the combustion states of water and diesel fuel are water droplet micro-explosion and extinction. The probability of the occurrence of micro-explosion will increase when the water droplet size decrease. In discussion on the diesel fuel and methanol we find strong and unstable micro-explosion. In the second part of this experiment, we find the difference of the concentration of water-methanol-premixture will affect the droplet collision and burning state.

並列關鍵字

combustion ； collision ； micro-explosion ； droplet

參考文獻

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