Files
Abstract
This thesis describes the development of a new macroscopic method to study thediffusion of particles using thermal imaging as a means of filtration. Using research previously conducted at The University of North Carolina at Charlotte as a basis for the experiment, ceramic grains in a vibratory polishing machine were used as a macroscopic analog for fluid molecules. A method of heating grains and using a thermal imaging camera to isolate the heated grains as they diffused was developed. Multiple methods of analyzing the video-data acquired during the experiment were tested, eventually resulting in an average grain diffusion by frame. A method was then developed to calculate the area of the diffusion event based upon the statistical probability of a particle being at a specific pixel location. This method was then modeled to determine the rate of particle diffusivity and, by using the Stokes-Einstein Relation, a diffusion coefficient, Dexperimental, was calculated. It was observed that the Dexperimental was orders of magnitude larger than expected; in attempting to explain this unexpected outcome, Dtheoretical was calculated and it was discovered that the diffusion does not appear to be thermally driven. Based on the highly dynamic nature of vibrating grains, a model was created to determine a kinetically driven diffusion coefficient we call ballistic self-diffusion, Dballistic. When comparing Dballistic to Dexperimental, it was found that they were on the same order of magnitude and both reflected within the linear modeling of the experimental data; this indicated that the dispersion event is most likely kinetically driven.