十六烷與醇類加入添加劑之液滴碰撞暨燃燒性質觀察研究

An Experimental Investigation on The Burning Characteristics of Collision –Merge Hexadecane / Alcohol of Additive

溫宏權(Hung Chuan Wen)

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.2004.01153

摘要

本實驗主要利用Ink-Jet printing method的原理以及新的碰撞機構，使得（可互溶或不可互溶）的兩顆不同組份的自由液滴在空中碰撞，經由液滴本身表面張力結合成多組份單一液滴後落入高溫含氧的燃燒環境中，觀察其各燃燒性質：點火延遲、燃燒速率、火焰縮口以及微爆現象。實驗過程將以可互溶與不可互溶為方向；兩過程使用油料皆以烷類‐N‐hexadecane（C16H34）與醇類‐甲醇、乙醇為主；在不可互溶中加入添加劑‐水、乙醇，試圖改變其原先之碰撞結果。另外利用添加劑 methyl tetra-butyl ether（MTBE）的加入，使得原先不互溶的烷類與醇類變成可互溶性質。在兩過程中皆針對不同的液滴尺寸、添加劑的體積比下，觀察其碰撞的結果以及碰撞後的燃燒現象。

根據實驗結果，無論是可互溶或是不可互溶液滴，在相互碰撞初期皆會將液滴周圍的空氣包覆進去使內部有小氣泡存在，若以存在的型態進入高溫環境，將容易產生微爆的機制。在可互溶液滴燃燒發現，在甲醇中加入適當體積比的MTBE將會使得原先不可互溶的液滴變成可互溶多組份液滴，進而觀察其燃燒現象。對於不可互溶液滴燃燒方面，發現加入添加劑‐水，會使得液滴在燃燒時的結合型態改變進而影響燃燒性質以及最重要的微爆性質。

關鍵字

添加劑 ； 微爆 ； 燃燒 ； 碰撞 ； 液滴

並列摘要

Experiment applies Ink-Jet Printing method and a new collision mechanism to makes two free droplets to collide in the air. After multiple ingredients of droplet is composed by surface tension, it fall into high temperature environment. We can observe the characteristics of combustion: ignition delay、burning time、burning rate、flame shrinkage and micro-explosion. It based on the mixable and non-mixable characteristics in this experiment. In this process, we observed the result and combustive phenomenon of collision under different size of droplet and volume ratio of surfactant.
According to our experiment results, the air surround the droplets can cover peripheral air, then form bubbles, no matter the droplets may dissolve or not, all has this phenomenon occurrence. If the droplets of that status fall into the high temperature environment, it will generate micro-explosion mechanism. We discover from mixable droplets combustion, if we join the MTBE of the suitable volume ratio, it will make non-mixable droplets become to multiple ingredients of mixable droplets. For non-mixable droplets combustion, if we join surfactant- water, it changes the combine status of droplets combustion and effect the combustion and micro-explosion characteristics.

並列關鍵字

additive ； combustion ； droplet ； micro-explosion ； collision

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