Weekly Seminar: Spring 2014
2013 Winner of the Corrsin-Kovasznay Outstanding Paper Award
Speaker: Dr. Sumedh R. Risbud (Massachusetts Institute of Technology)
Title: "Motion of a Suspended Particle Around an Obstacle at Zero Reynolds Number"
Date: Friday, March 7, 2014
Time: 11:00 a.m.
Location: Gilman Hall 50 (Marjorie M. Fisher Hall)
The effect of interactions experienced by a suspended particle and their influence on its trajectory around an obstacle in its path is investigated to gain an understanding of the motion of suspensions in porous media. Specifically, we have focused on a single spherical particle navigating around an obstacle of circular cross-section (a sphere or a cylinder). This can be thought of as the "dilute" limit of the problem under consideration. We will demonstrate that in this dilute limit, the distribution of particles around the obstacle is spherically symmetric. Furthermore, we show that the minimum separation with respect to the obstacle attained by the particle depends exponentially on the offset between the particle trajectory far upstream with respect to the obstacle and the obstacle centre. Finally, a model for effective surface roughness will be presented in terms of the aforementioned minimum separation and the net lateral displacement introduced in the particle trajectory downstream with respect to the obstacle.
Dr. Sumedh R. Risbud is a chemical engineer with expertise in fluid mechanics. He received his B. Tech. and M. Tech. in Chemical Engineering from Indian Institute of Technology Bombay (India) in 2008. In 2013, he received his Ph.D. in Chemical and Biomolecular Engineering from the Johns Hopkins University for his work on theoretical and computational investigation of particle motion at low/zero Reynolds number under the guidance of Prof. German Drazer (currently at the Department of Mechanical and Aerospace Engineering, Rutgers University). His doctoral research culminated in his dissertation titled 'Particle-Obstacle Interactions at Low Reynolds number: Implications for Microfluidic Applications’. Currently, he is working with Dr. James Swan at the Department of Chemical Engineering, Massachusetts Institute of Technology as a Postdoctoral Associate, where he is investigating the dynamics of field-assisted organization of active and passive colloids.