Date of Award
12-2016
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Mechanical Engineering
First Advisor
Arezoo M. Ardekani
Committee Chair
Arezoo M. Ardekani
Committee Member 1
John Patterson
Committee Member 2
Pavlos Vlachos
Committee Member 3
Steve Wereley
Abstract
Swimming motion of microorganisms, such as spermatozoa, plankton, algae and bacteria, etc., ubiquitously occurs in nature. It affects many biological processes, including reproduction, infection and the marine life ecosystem. The hydrodynamic effects are important in microorganism swimming, their nutrient uptake, fertilization, collective motions and formation of colonies. In nature, microorganisms have evolved to use various fascinating ways for locomotion and transport. Different designs are also developed for the locomotion of artificial nano- and microswimmers. In this study, we use several different computational models to investigate the behavior of microswimmers.
Microorganisms typically swim in the low Reynolds number regime, where inertia is negligible. They interact with each other, surfaces and external flow field. Microorganisms often swim in complex fluids, exhibiting non-Newtonian behavior, including viscoelasticity and shear-thinning viscosity. These biological materials contain network of glycoprotein fibers and gel-like polymers. Therefore on the scale of microorganisms, their fluid environments are heterogeneous rather than homogenous. In this study, we develop a computational platform to investigate swimming motion of a single and multiple microorganism(s) in the bulk fluid and near surfaces in complex fluids. We also investigate the role of fluid rheological properties and flow field on the migration of inert particles in a channel flow of viscoelastic fluids.
Recommended Citation
Li, Gaojin, "Hydrodynamics of swimming microorganisms in complex fluids" (2016). Open Access Dissertations. 965.
https://docs.lib.purdue.edu/open_access_dissertations/965