Research topics

The Continuum Mechanics Group has broad interests in a number of areas. This page collects a few of their recent results.


Rectified diffusion

Smith, W. R. & Wang, Q. X. 2022  A tractable mathematical model for rectified diffusion. Journal of Fluid Mechanics 951, 25, A12.

Diagram showing the growth of a bubble subject to an acoustic rectification over 6 million cycle of oscillation

 

The growth of a bubble subject to an acoustic rectification over 6 million cycles of oscillation. Our theory using matched asymptotic expansions in space and multi-scales in time correlates with experiments (cicles). This is the first rational model that predicts the development of ultrasound cavitation development. This milestone development will have long, wide and important impact in research and applications of ultrasound cavitation.

Bubble oscillation

Wang, Q. X., Liu, W.K., Corbett, C. and Smith, W. R. 2022 Microbubble dynamics in a viscous compressible liquid subject to ultrasound. Physics of Fluids 34, 012105

Sequence of images illustrating bubble dynamics mathematical research

Bubble oscillates subject to an acoustic wave. This is the only available numerical model that agrees excellently with experiment images for non-spherical bubbles in dozen cycles of oscillations.

Bubble dynamics near a rigid boundary

You, Y. Cui, J.,Smith, W. R. and Wang, Q. X. Computational and experimental study for bubble dynamics near a rigid boundary for a Reynolds number of O(10-100)

Diagram showing a vortex ring associated with a toroidal bubble

We show that a vortex ring associated with a toroidal bubble is not generated instantaneously as the liquid jet penetrates the bubble, as assumed for over a half of century, but develops within the bubble gas before that.