>Engineering, Human Science, Performing Arts

Dancing Motion of Bubbles and Cells

Project Description:

The dynamics of ultrasound-induced oscillating gas bubbles in a liquid subjected to acoustic field has been the subject of interest in many applications such as medical ultrasound field and has challenged scientists and engineers over several decades. A gas bubble which is excited by acoustic pressure moves toward or away from the pressure field. When the amplitude of acoustic pressure approaches a threshold value, the excited bubble begins to translate erratically. This phenomenon is called dancing motion of the bubble which is of great importance in many applications such as cell sorting; where it is believed that the cells are behaving similar to bubbles. The parametrically excited shape oscillations of a gas bubble caused by its radial pulsation in a standing sound wave, leads to its translational instability and hence dancing motion.

Many bio-medical applications entail the problems of spatially manipulating of bubbles and cells by means of acoustic radiation. The examples are ultrasonic noninvasive-targeted drug delivery and therapeutic applications. This proposal investigates the coupling between radial pulsations, axisymmetric modes of shape oscillations and translational motion of a single spherical gas bubble in a host liquid, when it is subjected to an acoustic pressure wave field. Instability of the shape modes of a bubble, which is contributing to form the translational instability, known as dancing motion, will be analyzed. Thus, in this proposed work, we will leverage our resources from a interdisciplinary collaboration including Biomedical Engineering, Medicine, and Performing Arts to understand how bubbles feature a surprising collective dance movement. The movement styles in dancing motion of a bubble in a controlled acoustic field will be translated to analyze the motion where they interact without contact and the equilibrium distance can be adjusted by simply tuning the acoustic frequency.  

Interdisciplinary aspects involve students from different disciplines of school of Engineering, Medicine and School of Arts. This project will be done in four phases: (1) design (two months), (2) fabrication (two months) and (3) operation of microfluidic channels with bubbles and cells (four months), and (4) analyzing the dancing motions of bubbles and cells in channels and final reports (four months). The microfluidic channels will be designed first based on the numerical analysis. Then silicon wafer molds for the microfluidic channels will be  fabricated in VT Micro & Nano Fabrication Laboratory. The PIs will jointly supervise the research effort and the graduate students involved. The undergraduate students will work collaboratively in order to maximize fully integrated and multidisciplinary research activities. Progress group meetings will be held twice a month, and students will present recent progress.

Dr. Shima Shahab, Department of Biomedical Engineering and Mechanics
Dr. Rafael Davalos, Department of Biomedical Engineering and Mechanics
Dr. Billie Lepczyk, School of Performing Arts

Collaborative Colleges:

Human Science
Performing Arts