Date of Completion


Embargo Period



Anson Ma, Xinyu Zhao, Ying Li

Field of Study

Mechanical Engineering


Master of Science

Open Access

Campus Access


Theoretical investigation is presented for a linear viscoelastic flow induced by an oscillatory colloidal particle in nonadsorbing polymer solutions. At small-amplitude oscillation, the polymer distribution is assumed at equilibrium and forms a depletion zone around the particle based on polymer mean field approximation. A simplified two-layer approximation is compared with numerical results using a continuous depletion profile to describe the nonuniform complex viscosity. The goal is to present the apparent complex viscosity sensed by the particle and to distinguish it from the actual viscosity of the bulk fluid. The resulting friction coefficient can be used to interpret active or passive microrheological measurement that takes polymer depletion into account.

Major Advisor

Tai-Hsi Fan