201. Controllable direction of liquid jets generated by thermocavitation within a droplet
- Author
-
Nikolai Korneev, Julio C. Ramirez-San-Juan, J. P. Padilla-Martinez, Ruben Ramos-Garcia, Guillermo Aguilar, Carla Berrospe-Rodriguez, and P. Zaca-Morán
- Subjects
Shock wave ,Materials science ,Bubble ,Astrophysics::High Energy Astrophysical Phenomena ,02 engineering and technology ,Optical Physics ,01 natural sciences ,Physics::Fluid Dynamics ,Optics ,0103 physical sciences ,Electrical and Electronic Engineering ,010306 general physics ,Engineering (miscellaneous) ,Jet (fluid) ,business.industry ,Mechanical Engineering ,021001 nanoscience & nanotechnology ,Atomic and Molecular Physics, and Optics ,Ray tracing (physics) ,Surface wave ,Reflection (physics) ,0210 nano-technology ,business ,Acoustic impedance ,Body orifice - Abstract
A high-velocity fluid stream ejected from an orifice or nozzle is a common mechanism to produce liquid jets in inkjet printers or to produce sprays among other applications. In the present research, we show the generation of liquid jets of controllable direction produced within a sessile water droplet by thermocavitation. The jets are driven by an acoustic shock wave emitted by the collapse of a hemispherical vapor bubble at the liquid-solid/substrate interface. The generated shock wave is reflected at the liquid-air interface due to acoustic impedance mismatch generating multiple reflections inside the droplet. During each reflection, a force is exerted on the interface driving the jets. Depending on the position of the generation of the bubble within the droplet, the mechanical energy of the shock wave is focused on different regions at the liquid-air interface, ejecting cylindrical liquid jets at different angles. The ejected jet angle dependence is explained by a simple ray tracing model of the propagation of the acoustic shock wave inside the droplet.
- Published
- 2017