Author's School

School of Engineering & Applied Science

Author's Department/Program

Energy, Environmental and Chemical Engineering

Language

English (en)

Date of Award

5-24-2010

Degree Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Chair and Committee

Milorad Dudukovic

Abstract

In this study we develop the computational and experimental tools to assist us in performance evaluation of trickle bed reactors: TBRs). The study focuses on experimental characterization of the flow distribution, and development of computational fluid dynamics: CFD) model of trickle flow. The experimental study has been performed to examine the quality of liquid phase distribution in a high pressure system. The results were provided in terms of distribution of the effluent liquid fluxes and cross-sectional liquid holdups. Their individual trends, but also their relation with respect to operating conditions was examined. Characterization of bed porosity distribution has been performed and used as the input to the computational model. The experimental study of the dependence of the extent of hysteresis on operating parameters in a high pressure TBR was performed. The extent of hysteresis was found uniquely determined by the pressure drop in the Levec prewetting mode. This fact and developed CFD model were then used to deduce conditions leading to operation with negligible hysteresis effects. Three-dimensional Eulerian CFD model is developed. Phase interaction closures are based on the film flow model, principles of statistical hydrodynamics and relative permeability concept. Model has been assessed against experimental data for liquid holdup, wetting efficiency and pressure drop hysteresis. Hydrodynamic Eulerian CFD model is then used together with species balance to examine the TBR performance for gas and liquid reactant limited systems. For each case a closed form approach of coupling bed and particle scale solution within CFD framework was presented.

Comments

Permanent URL: http://dx.doi.org/10.7936/K7WQ01V5

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