雙組份生質柴油與柴油液滴於高溫環境下 之燃燒現象觀察與研究

On the Burning Characteristics of Diesel and Bio-Diesel Binary Fuel Droplets

張仁和(Ren-He Chang)

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(2008年)

https://doi.org/10.6342/NTU.2008.01706

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，觀察液滴在撞擊後之燃燒性質:點火延遲、燃燒時間、火焰縮口、微爆現象以及燃燒速率。實驗中第一部分以水、甲醇、乙醇分別和生質柴油與柴油碰撞燃燒，使用不同的燃油體積比例和氧氣濃度，觀察其燃燒現象，第二部份則將大豆油、橄欖油以及石蠟烷油分別和生質柴油和柴油預混燃燒，來探討其替代能源之可能性。
實驗結果發現，水分別和生質柴油與柴油撞擊燃燒後會有水滴微爆與熄滅兩種情況，微爆出現機率與水的體積大小成反比。甲醇、乙醇、水和生質柴油碰撞後燃燒皆有發現縮口之現象。生質柴油與柴油中加入大豆油和橄欖油都增加了其燃燒時間。

關鍵字

液滴 ； 撞擊 ； 燃燒 ； 微爆 ； 火焰縮口

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. Then We can observe the characteristics of combustion including ignition delay, burning time, flame shrinkage, explosion and burning rate. In the first part of experiment, We use water, methanol, and ethanol to collide with bio-diesel and diesel respectively, and use different droplet volume fraction, oxygen volume fraction to observe the characteristics of combustion. In the second part, we use salad oil, olive oil, and paraffin oil to mix with bio-diesel and diesel respectively then observe the characteristics of premixture and discuss the feasibility of alternative energy.

The experiment reveals that the states of water and bio-diesel are droplet micro-explosion and droplet extinction. The probability of the occurrence of micro-explosion will increase with decreasing the water droplet size. We can find the burning characteristics when methanol, ethanol, water collide with bio-diesel respectively is flame shrinkage. We find the burning time increase when we use salad oil, olive oil, and paraffin oil to mix with bio-diesel and diesel.

並列關鍵字

droplet ； collision ； combustion ； micro-explosion ； flame shrinkage

參考文獻

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