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dc.contributor.advisor Balakotaiah, Vemuri
dc.creator Ratnakar, Ram
dc.date.accessioned 2012-06-28T18:42:55Z
dc.date.available 2012-06-28T18:42:55Z
dc.date.created 2012-05
dc.date.issued 2012-06-28
dc.date.submitted May 2012
dc.identifier.uri http://hdl.handle.net/10657/ETD-UH-2012-05-442
dc.description.abstract In the first part, a systematic procedure of multi-scale averaging, based on Lyapunov-Schmidt (L-S) technique of bifurcation theory, is presented where low-dimensional models are derived for two problems: dispersion of a non-reacting tracer in laminar flow in a tube (Taylor dispersion); and, diffusion, convection and reaction in a catalytic monolith with porous washcoat. The averaged model for Taylor dispersion developed by the L-S procedure is exact for general inlet/initial conditions including point sources. It predicts no centroid displacement or variance deficit as other models in the literature. Truncated hyperbolic models are also presented along with inlet/initial conditions to the same accuracy. The reduced order model developed for catalytic monoliths is presented in terms of three concentration modes and it is shown for time-varying inlet conditions, the interfacial flux depends on all three modes. In such cases, in contrast to the traditional two-phase model, the three-mode reduced order model retains the feature of the detailed model. In the second part, modeling and simulation of reactive dissolution of carbonates with in-situ gelling acids is presented. Stimulation of oil-wells in carbonate-reservoirs using an acidic-solution is a common practice to enhance oil production. However, due to heterogeneity, acid flows preferentially in high-permeability zones, which results into under stimulation of low-perm regions. Therefore, in-situ gelling acids are used that block the high-permeability region by forming a gel and diverts more acid to the low-permeability zones. Here, a rheological model for in-situ gelling acids is developed and combined with an extended two-scale-continuum model to describe the transport and reaction of in-situ gelling acids in carbonates. Three-dimensional simulations predict dissolution patterns in various flow regimes that are in accordance with experimental results. The effect of rheological parameters on flow diversion, optimum injection rates, wormhole diameter and gel front-width and speed is studied using scaling analysis. Finally, guidelines for optimal stimulation of carbonates with in-situ gelling acids are presented.
dc.format.mimetype application/pdf
dc.language.iso eng
dc.subject Multi-scale Averaging
dc.subject Lyapunov-Schmidt Technique
dc.subject Low-dimenional Model, Diffusion
dc.subject Dispersion
dc.subject Convection
dc.subject Reaction
dc.subject Mathematical Modeling
dc.subject Laminar Flow
dc.subject Monoliths, Transfer Coefficients
dc.subject Hyperbolic Models
dc.subject Parabolic Models
dc.subject Multimode Models
dc.subject Regularization
dc.subject Moment Analysis
dc.subject Carbonate Reservoirs
dc.subject Acidization
dc.subject Wormhole
dc.subject Pattern Formation
dc.subject Porous Media
dc.subject Rheology
dc.subject Two-Scale Continuum Model
dc.subject Simulations
dc.subject In-situ Gelling Acids
dc.subject Scaling Analysis
dc.title Multi-scale Averaging and Analysis of Transport and Reaction Phenomena in Porous Media
dc.date.updated 2012-06-28T18:43:03Z
dc.identifier.slug 10657/ETD-UH-2012-05-442
dc.type.material text *
dc.type.genre thesis *
thesis.degree.name Chemical ENGR (PhD)
thesis.degree.level Doctoral
thesis.degree.discipline Chemical Engineering
thesis.degree.grantor University of Houston
thesis.degree.department Chemical and Biomolecular Engineering
dc.contributor.committeeMember Luss, Dan
dc.contributor.committeeMember Economou, Demetre J.
dc.contributor.committeeMember Mohanty, Kishore K.
dc.contributor.committeeMember Nasr-El-Din, Hisham A.

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