Heterogeneity of surfaces is often included in mathematical treatments of colloid transport and deposition as an afterthought, if at all. Most previous models of colloid transport and deposition have employed idealizations and simplifications such as assuming smooth collector surfaces with uniform chemical properties. This research proposes a new heterogeneous interaction model (HIM) to account for colloidal forces between particles and heterogeneous substrates. Extending the approach employed with the HIM, the inclusion of convection and diffusion in the model leads to a Lagrangian particle tracking model (PTM) for predicting colloid transport and deposition on a planar substrate containing one or more protruding asperities in the presence of shear flow. An important part of the PTM is an accurate rendering of the fluid flow field around the model substrate, which is obtained from a numerical solution of the Stokes equations. A simple approximation of the particle-substrate hydrodynamic interactions was developed for the PTM based on the universal hydrodynamic correction functions. This model was employed to quantitatively predict how presence of asperities on a collector can influence the deposition of particles on the substrate in shear flow. Flow field modifications due to the substrate's physical heterogeneity -- coupled with hydrodynamic interactions -- and the lateral migration (colloidal) forces near chemically heterogeneous substrates yield remarkably diverse deposition probabilities and deposit morphologies. The general approach of this research, which involves the use of the HIM in conjunction with the Brownian PTM, results in the first simulation tool of its kind to attempt to quantify deposition on heterogeneous substrates.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:AEU.10048/866 |
| Date | 06 1900 |
| Creators | Kemps, Jeffrey A L |
| Contributors | Bhattacharjee, Subir (Mechanical Engineering), Kostiuk, Larry (Mechanical Engineering), Tang, Tian (Mechanical Engineering), Lipsett, Michael (Mechanical Engineering), Yeung, Anthony (Chemical Engineering), Tufenkji, Nathalie (Chemical Engineering, McGill University) |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | 20985155 bytes, application/pdf |
| Relation | Kemps, Jeffrey A. L. and Bhattacharjee, Subir (2005). Langmuir, Kemps, Jeffrey A. L. and Bhattacharjee, Subir (2009). Langmuir |
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