Heat transfer in canned particulate system in Newtonian and non-Newtonian liquids was studied during end-over-end agitation thermal processing in a pilot scale rotary retort. Computational methods for conventional overall heat transfer coefficient (U) and fluid to particle heat transfer coefficient (hfp) were found unsuitable in high viscosity fluids. A methodology for evaluating an apparent heat transfer coefficient (hap) between retort medium and particle, and an apparent overall heat transfer coefficient Ua between retort medium and can fluid was proposed. Use of h ap and Ua concepts permitted direct predictions of particle temperature and lethality based on retort temperature. / An L-16 orthogonal experimental design of experiments was carried out to select system factors that significantly affected hap and U a values for particles in high viscosity non-Newtonian and Newtonian fluids. Experiments using central composite rotatable design and full factorial design were carried out to study the effects of selected significant factors on hap and Ua. / Using all data obtained, dimensionless correlations were developed for the prediction of hap and Ua values. The developed correlations showed a good agreement with the experimental data. More precise predictions were achieved with trained artificial neural network (ANN) models. The results of ANN models could be compiled using algebraic equations and were included so that hap and Ua values could be predicted without actually using the ANN software. A flow visualization study was conducted to better understand the heat transfer behavior in high viscosity fluids. Results showed that in particulate high viscosity fluids, the particle liquid relative movement was very weak, implying that the heat transfer between them could converge to conduction-conduction rather than convection-conduction, which results in erroneous and unusually large hfp values.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.100655 |
| Date | January 2006 |
| Creators | Meng, Yang, 1968- |
| Publisher | 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 | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Food Science and Agricultural Chemistry.) |
| Rights | © Yang Meng, 2006 |
| Relation | alephsysno: 002479161, proquestno: AAINR25208, Theses scanned by UMI/ProQuest. |
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