Record Details
Computational fluid dynamics analysis of air-water bubble columns
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Computational fluid dynamics analysis of air-water bubble columns |
| Names |
Monahan, Sarah Marie
(creator) |
| Date Issued | 2007 (iso8601) |
| Note | Access restricted to the OSU Community |
| Abstract | "This thesis includes seven chapters. Chapter 2 provides a review of bubble column simulations reported in the literature. Chapter 3 contains a detailed description of the two-fluid model implemented in CFDLib with an emphasis on the closure models applied in our numerical studies. Additionally, the major subroutines and the discretization scheme within CFDLib are explained. Chapter 4 discusses the characteristics of the homogeneous, transitional, and heterogeneous flow regimes, and then focuses on the ability of the two-fluid model to predict the behavior of these flow regimes. A detailed analysis shows that the flow predictions are highly dependent on the model formulation (i.e., bubble-induced turbulence, drag, lift, rotation, strain, virtualmass), as well as parameters such as bubble size and liquid coflow. Scale-up to larger column diameters for the flow regimes is also studied. Chapter 5 presents a further analysis of the effect of the two-fluid model formulation on bubble-column flow-regime predictions. Simulations are presented in the form of flow maps, which show the flow behavior expected for a particular value of the bubble Reynolds number and the average void fraction. A particular set of model parameters shows qualitative agreement with experiments performed at Delft University of Technology. Chapter 6 describes how linear stability analysis can be used to determine the stability of the two-fluid model applied toward the CFD predictions. The derivation of the dispersion relations corresponding to the two-fluid model used in this work is presented. Chapter 7 presents a validation study of our results against those of the experimental research group at Delft University of Technology. Specifically, we focus on their rectangular pseudo-twodimensional column in which non-homogeneous flow can be obtained by changing the aeration pattern. Chapter 8 summarizes the major conclusions and discusses recommendations for future work."--P. 4. |
| Genre | Thesis |
| Topic | Two-phase flow |
| Identifier | http://hdl.handle.net/1957/50735 |
