Interfacial flow and instability of ultra-high pressure liquid jets (NSFC 51176065)

Research Area: Fluid mechanics
Project Members:
Wang, Y.W.

Project Description

The jet instability and breakup are critical issues bonding to ultra-high pressure waterjet technologies. This project intend to study the capillary liquid jet at ultrahigh pressure levels (100 ~ 400 MPa). State-of-art measurement and visualization techniques will be employed to explore the physics, in particular the hydrodynamics involved in the jet ejection process. The core part of this proposal focuses on the flow structure and turbulence in the jet periphery. Detailed researches cover the jet primary breakup mode, the effect of interfacial turbulence on the jet instability, the evolution of the disturbed liquid-gas interface, the droplet formation and pinch-off during the primary breakup. The scale effect on jet breakup is also under consideration. The entire work aims to reveal the instability and breakup mechanisms and set up a mathematical expression demonstrating evolution of jet interface before primary breakup. Potential achievements also include a definition of the breakup mode of ultra-high pressure fine liquid jet, together with a feature number that could accurately represent the characteristics of this mode. It is expected this project could bring a breakthrough on the flow dynamics of super high pressure liquid jet, extend the framework of jet instability theory and rise innovative ideas of flow control that would help improve the water jet machining technique.

Publications related to the project

2016Experimental study of jet surface structures and the influence of nozzle congfiuration
Fluid Dynamics Research 48  (Published)
2015The acquisition and measurement of surface waves of high-speed liquid jets
Journal of Visualization  1-14 (Published)
2015Wavelength measurement of a liquid jet based on spectral analysis of image intensity
Advances in Mechanical Engineering 7(8) 1-10 (Published)

Internal Reports related to the project

YearTitleDocument Type