Quantitative observation on characteristics and breakup of single superheated droplet
Quantitative observation on characteristics and breakup of single superheated droplet
复制标题
单个过热液滴特性及破碎的定量观察
DOI：
10.1016/j.expthermflusci.2016.09.004
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发表时间：
2017
影响因子：
3.2
通讯作者：
Bin Xu
中科院分区：
文献类型：
--
作者：
Shiyan Li;Yuyin Zhang;Wenyuan Qi;Bin Xu
闪急沸腾雾化是一种有效的雾化方式，它通过引入气泡的爆炸来增强燃油射流的破碎，从而改善燃油喷雾的蒸发。然而，过热射流的破碎机理，特别是与液滴内部汽泡爆炸有关的机理，至今仍不清楚。本研究开发了一种过热液滴发生器，利用显微成像技术观察过热液滴内部汽泡产生的液滴形态变化和破碎过程。结果表明，液滴温度对液滴形态有重要影响，而温度对液滴中微气泡的形成和过热液滴的破碎有重要影响，温度为25 ℃时，由于空泡率不断增大，超过50%左右，是液滴发生破碎的重要临界点破碎模式从空气动力学模式转变为热力学模式。过热液滴的表面张力也是液滴形态，并且结果表明，表面张力的最大降低达到。70%，作为蒸发度增加到约25 C，并且这解释了SMD的急剧下降。对于闪速沸腾喷雾，当蒸发度接近这个水平时。evaluated.by这些结果为理解过热液滴和液体射流的破碎机理及其建模提供了有意义的信息。
Flash-boiling atomization is an effective way to enhance fuel jet breakup by introducing explosion of.vapor bubbles and thus improve the evaporation of fuel spray, compared with the conventional high.pressure injection. However, the break-up mechanism of a superheated jet, especially, that associated.with the explosion of vapor bubbles inside the droplets, is still unknown. In this study, a superheated droplet.generator was developed for observing the droplet morphology variation and the breakup process.resulting from the vapor bubbles inside a superheated droplet by microscopic imaging. It was found that.the droplet morphology is mainly influenced by droplet temperature, but micro bubbles formation and.the breakup of the superheated droplet are dominated by superheat degree, and the superheat degree.of 25 C is an important critical point at which the droplet breakup occurs resulted from the everincreasing.void fraction exceeding a value of approximately 50% and the breakup mode shifts from aerodynamic.mode to thermodynamic mode. The surface tension of superheated droplet was also evaluated.by the droplet morphology, and the results show that the maximum reduction in surface tension reaches.70% as superheat degree increases to approximately 25 C, and this explains the sharp decrease in SMD.for a flash boiling spray when the superheat degree approaches this level. These results provide insightful.information for understanding the breakup mechanism of superheated droplets and liquid jet and its.modeling.
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影响因子：
64.8
作者：
W. D. Harkins
通讯作者：
W. D. Harkins
影响因子：
2
作者：
R. D. Oza
通讯作者：
R. D. Oza
DOI：
10.1016/j.proci.2012.07.061
发表时间：
2013
期刊：
--
影响因子：
--
作者：
W. Zeng;Min Xu;Yuyin Zhang;Zhenkan Wang
通讯作者：
W. Zeng;Min Xu;Yuyin Zhang;Zhenkan Wang
DOI：
10.1299/jsmeb.37.313
发表时间：
1994-05
期刊：
Jsme International Journal Series B-fluids and Thermal Engineering
影响因子：
--
作者：
E. M. Peter;A. Takimoto;Y. Hayashi
通讯作者：
E. M. Peter;A. Takimoto;Y. Hayashi
DOI：
10.1021/i100022a005
发表时间：
1986-05
期刊：
Industrial & Engineering Chemistry Fundamentals
影响因子：
--
作者：
Y. Kitamura;H. Morimitsu;Teruo Takahashi
通讯作者：
Y. Kitamura;H. Morimitsu;Teruo Takahashi