雙組份柴油撞擊液滴之碰撞現象觀察

An experimental investigation on the coalescent behavior of multi-component diesel fuel/liquid collision

黃偉豪(Wei–Hao Huang)

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.2004.00922

摘要

中文摘要
本文主要實驗觀察雙顆液滴的碰撞。以柴油（Diesel Fuel）為主，分別與可溶、不可溶及預混好的溶液相互撞擊。實驗油料方面，選用相溶性的丙醇(C3H7OH)，不相溶性的水(H2O)、甲醇(CH3OH)、乙醇(C2H5OH)及預混溶液的甲醇+水、乙醇＋水、甲醇＋乙醇、丙醇＋甲醇，分別探討在不同的撞擊速度、尺寸及撞擊參數下的碰撞情形。
實驗發現，相溶性油料的碰撞如同前人觀察直鍊烷類碰撞一樣，最後會混合成一顆球形的液滴。而不相溶部分就較為複雜，例如：柴油和水在不同的相對速度、擦撞係數下會有彈開、拉伸分離現象，而柴油和甲醇在不同的相對尺寸下會產生包覆和黏合的現象。
在預混溶液方面，以不同的相對尺寸探討每個不同濃度的預混溶液與柴油的碰撞情形，著重於觀察結合後為包覆、黏合及混合的現象。

關鍵字

撞擊 ； 液滴 ； 包覆 ； 黏合

並列摘要

Abstract
In this paper we experiment on the collision of two droplets and observe the behavior of collision. We take diesel fuel as the principal component and make it collide with the miscible, non-miscible and the pre-mixed droplets item by item. Regarding to the fuel in the experiment, we use the miscible 1-propanol, the non-miscible methanol, ethanol, water and the pre-mixed liquid--- methanol + water, ethanol + water, methanol + ethanol, 1-propanol + methanol. And then, we discuss their behavior of collision by changing the speed of collision, the size of the droplets and the impact parameter.

We found that the droplets of miscible fuels will intermix into one at last just like those of alkanes investigated by pervious researchers. However, the situation of non-miscible droplets is more complicated. For instance, the multi-component diesel fuel/water will bounce and off-centre separate at different relative speed and on different impact parameter. As for the diesel fuel/methanol, they insert and adhere to each other at different size.

Finally, as far as the pre-mixed liquids concerned, we change the concentration and size of the diesel fuel/pre-mixed liquids to make emphasis on the observation of the behavior of bouncing, coalescence and mixing.

並列關鍵字

collision ； droplet ； adhesive ； insertion

參考文獻

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