On explosive boiling of a multicomponent Leidenfrost drop
| Autor: | Sijia Lyu, Chao Sun, Chung K. Law, Xianjun Yang, Yuki Wakata, Huanshu Tan, Detlef Lohse |
|---|---|
| Přispěvatelé: | MESA+ Institute, Physics of Fluids |
| Rok vydání: | 2021 |
| Předmět: |
Multidisciplinary
Materials science volatility differentials Explosive material Mutual solubility differential Drop (liquid) multicomponent drop internal interaction Evaporation Fluid Dynamics (physics.flu-dyn) FOS: Physical sciences Physics - Fluid Dynamics Mechanics Combustion Leidenfrost effect Superheating Boiling Oil droplet Physical Sciences mutual solubility differentials Leidenfrost state |
| Zdroj: | Proc Natl Acad Sci U S A Proceedings of the National Academy of Sciences of the United States of America, 118(2):e2016107118. National Academy of Sciences |
| ISSN: | 1091-6490 0027-8424 |
| Popis: | The gasification of multicomponent fuel drops is relevant in various energy-related technologies. An interesting phenomenon associated with this process is the self-induced explosion of the drop, producing a multitude of smaller secondary droplets, which promotes overall fuel atomization and, consequently, improves the combustion efficiency and reduces emissions of liquid-fueled engines. Here, we study a unique explosive gasification process of a tricomponent droplet consisting of water, ethanol, and oil ("ouzo"), by high-speed monitoring of the entire gasification event taking place in the well-controlled, levitated Leidenfrost state over a superheated plate. It is observed that the preferential evaporation of the most volatile component, ethanol, triggers nucleation of the oil microdroplets/nanodroplets in the remaining drop, which, consequently, becomes an opaque oil-in-water microemulsion. The tiny oil droplets subsequently coalesce into a large one, which, in turn, wraps around the remnant water. Because of the encapsulating oil layer, the droplet can no longer produce enough vapor for its levitation, and, thus, falls and contacts the superheated surface. The direct thermal contact leads to vapor bubble formation inside the drop and consequently drop explosion in the final stage. Comment: 8 pages, 5 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|