雙組份生質柴油於高溫環境下之燃燒現象觀察與研究

An Experimental Investigation on the Burning Characteristics of Collision-Merged Bio-Diesel Fuel Droplets

蔡承豐(Cheng-Feng Tsai)

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(2007年)

https://doi.org/10.6342/NTU.2007.02273

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，觀察其各燃燒性質：點火延遲、燃燒時間、燃燒速率、火焰縮口、以及微爆現象。實驗中第一部分以高級柴油、生質柴油與不可燃性液體Water（H2O）為主，在不同的比例、氧氣濃度下，觀察其燃燒與微爆現象，第二部份則將生質柴油和甲醇、乙醇，也是在不同比例、氧氣濃度下，觀察其預混與碰撞的差異。
實驗結果發現，水與生質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，且有火焰縮口的現象發生。甲醇、乙醇與生質柴油撞擊、燃燒、微爆的穩定度優於柴油。

關鍵字

液滴 ； 碰撞 ； 燃燒 ； 微爆 ； 生質柴油

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. We can observe the characteristics of combustion : ignition delay、burning time、burning rate、flame shrinking and micro-explosion. We use diesel fuel, bio-diesel, and water in the first part of this experiment. In different droplet size, oxygen volume fraction observe the characteristics of combustion and micro-explosion. Use bio-diesel and methanol, ethanol in the second part. Then we can observe the characteristics of premixture and collision.
According to the experiment results, the combustion states of water and bio-diesel are water droplet micro-explosion and extinction. The probability of the occurrence of micro-explosion will increase when the water droplet size decrease. Then find flame shrinking in this experiment. The methanol, ethanol and bio-diesel collision、combustion、micro-explosion stability better than diesel.

並列關鍵字

droplet ； collision ； combustion ； micro-explosion ； Bio-diesel

參考文獻

1.T.B.Low and R.List,“Collision ,Coalescence and Breakup of Raindrops. Part2: Parameterization of Fragment Size Disturbution,”J. Atm. Sci., Vol.39,pp.1607-1618,(1982).

3.N.Ashgriz and J.Y.Poo,“Coalescence and Separation in Binary Collisions of Liquid Droplets,”J Fluid Mech,Vol.221,pp.183-204,(1990).

4.Y.J.Jiang,A.Umemura and C.K.Law,“An Experimental Investiagation on the Collision Behavior of Hydrocarbon Droplets,”J Fluid Mech,Vol. 234,pp.171-190,(1992).

5.C.K.Law and H.K.Law,“A d2-Law for Multicomponent Droplet Vaporization and Combustion,”AIAA Journal,Vol.20,NO.4,pp.522, (1982).

8.B.J.Wood and W.A.Rosser,“An experimental study of fuel dropletignition,”AIAA Journal,Vol.7,pp.2288-2300,(1969).