| Author: | Li, Tianyao |
| Title: | Numerical investigation on the head-on droplet collisions under elevated pressures using front-tracking method |
| Advisors: | Zhang, Peng (ME) |
| Degree: | M.Sc. |
| Year: | 2017 |
| Subject: | Hong Kong Polytechnic University -- Dissertations Drops -- Mathematical models Fluid dynamics |
| Department: | Faculty of Engineering |
| Pages: | v , 93 pages : color illustrations |
| Language: | English |
| Abstract: | Droplet collision is a common phenomenon in many natural and industrial fluid dynamics. Most recently, droplet collision in high pressure gas-liquid hydrocarbon systems becoming a topic of interest in many industry applications. Studies on the collision and bouncing of droplets will promote the understanding of these processes and provide theoretical support for various engineering applications and designs. The bouncing of binary droplets is simulated using front tracking method. The effect of gas pressure, Weber number and size ratio on the bouncing process are investigated. The results showed that the deformation ratio of droplets decreases with the increase of gas pressure. Through the evolution of energy budget, it is found that the higher pressure condition has no effect on the length of squeeze period but lengthen rebounding period of bouncing. On the other hand, viscosity dissipation rate drops with the increasing of air pressure. Meanwhile, “Hysteresis” phenomenon of the interfaces can be clearly captured in the simulation results. It is found that “hysteresis” is a nonmonotonic problem that is affected by both Weber number and air pressure. Three regimes of Hysteresis distance Δh had been developed in the space of We (2.27-17)- P (2-50 atm), which includes (I) Positive correlation between Δh and P; (II) Nonoccurrence of hysteresis and (III) Negative correlation between Δh and P. |
| Rights: | All rights reserved |
| Access: | restricted access |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| 991021962224503411.pdf | For All Users (off-campus access for PolyU Staff & Students only) | 5.19 MB | Adobe PDF | View/Open |
Copyright Undertaking
As a bona fide Library user, I declare that:
- I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
- I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
- I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.
By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.
Please use this identifier to cite or link to this item:
https://theses.lib.polyu.edu.hk/handle/200/9069