SUBJECT: Ph.D. Proposal Presentation
BY: Yuanzheng Zhu
TIME: Wednesday, September 13, 2017, 3:00 p.m.
PLACE: Love Building, 210
TITLE: Multi-scale Computational Modeling of Particle Adhesion Dynamics Under Shear Flow
COMMITTEE: Dr. Cyrus Aidun, Chair (ME)
Dr. David Ku (ME)
Dr. Marc Smith (ME)
Dr. Richard Vuduc (CSE)
Dr. Wilbur Lam (Emory/Georgia Tech)


Adhesion of particles to surfaces under shear occurs in many industrial and biological flows. The key components in these systems usually covers a wide range of length scales. Consider the particle adhesion in falling film flow, where the film thickness is in the order of millimeters, the particles/crystals are micron size, and adhesion occurs in sub-micron range. In blood flow, the vessel, cells, nanoparticles and receptor-ligand bonds are ~10^-3 m, ~10^-5 m, ~10^-7 m, and ~10^-8 m, respectively. It becomes computationally expensive to explicitly resolve all the scales in these flows. To address this challenge, firstly, a multiscale numerical model will be developed to simulate systems covering 4~5 orders of magnitude in length scale, by coarse-graining small particles as governed by Brownian Dynamics. The off-lattice nano-sized particles are coupled with fluid phase, and interact with micro-sized particles by pair-wise physical bonds and adhesion forces. Next, this model will be validated by comparing experimental data for platelets adhesion process in thrombosis, and comparing semi-empirical model of crystal scale formation on evaporator surface. Finally, predictive simulations will be performed to gain deeper insights into the physics of particle adhesion dynamics in both blood flow and evaporator falling film flow near surfaces.